Lymphatic and blood endothelial cell genes

ABSTRACT

The invention provides polynucleotides and genes that are differentially expressed in lymphatic versus blood vascular endothelial cells. These genes are useful for treating diseases involving lymphatic vessels, such as lymphedema, various inflammatory diseases, and cancer metastasis via the lymphatic system.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to polynucleotides and proteins specifically expressed in lymphatic endothelial cells.

2. Description of the Related Art

Recent evidence on the association of lymphangiogenic growth factors with intralymphatic growth and metastasis of cancers (Mandriota, et al., EMBO J. 20:672-682 (2001); Skobe, et al., Nat. Med. 7:192-198 (2001); Stacker, et al., Nat. Med. 7:186-191 (2001);. Karpanen, et al., Cancer Res. 61:1786-1790 (2001)) has raised hopes that lymphatic vessels could be used as an additional target for tumor therapy. Cancer cells spread within the body by direct invasion to surrounding tissues, spreading to body cavities, invasion into the blood vascular system (hematogenous metastasis), as well as spread via the lymphatic system (lymphatic metastasis). Regional lymph node dissemination is the first step in the metastasis of several common cancers and correlates highly with the prognosis of the disease. The lymph nodes that are involved in draining tissue fluid from the tumor area are called sentinel nodes, and diagnostic measures are in place to find these nodes and to remove them in cases of suspected metastasis. However, in spite of its clinical relevance, little is known about the mechanisms leading to metastasis via the bloodstream or via the lymphatics.

Until recently, the lymphatic vessels have received much less attention than blood vessels, despite their importance in medicine. Lymphatic vessels collect protein-rich fluid and white blood cells from the interstitial space of most tissues and transport them as a whitish opaque fluid, the lymph, into the blood circulation. Small lymphatic vessels coalesce into larger vessels, which drain the lymph through the thoracic duct into large veins in the neck region. Lymph nodes serve as filtering stations along the lymphatic vessels and lymph movement is propelled by the contraction of smooth muscles surrounding collecting lymphatic vessels and by bodily movements, the direction of flow being secured by valves as it is in veins. The lymphatic capillaries are lined by endothelial cells, which have distinct junctions with frequent large interendothelial gaps. The lymphatic capillaries also lack a continuous basement membrane, and are devoid of pericytes. Anchoring filaments connect the abluminal surfaces of lymphatic endothelial cells to the perivascular extracellular matrix and pull to maintain vessel patency in the presence of tissue edema. The absence or obstruction of lymphatic vessels, which is usually the result of an infection, surgery, or radiotherapy and in rare cases, a genetic defect, causes accumulation of a protein-rich fluid in tissues, lymphedema. The lymphatic system is also critical in fat absorption from the gut and in immune responses. Bacteria, viruses, and other foreign materials are taken up by the lymphatic vessels and transported to the lymph nodes, where the foreign material is presented to immune cells and where dendritic cells traverse via the lymphatics. There has been slow progress in the understanding of and ability to manipulate the lymphatic vessels.

Abnormal development or function of the lymphatic ECs can result in tumors or malformations of the lymphatic vessels, such as lymphangiomas or lymphangiectasis. Witte, et al., Regulation of Angiogenesis (eds. Goldber, I. D. & Rosen, E. M.) 65-112 (Birkauser, Basel, Switzerland, 1997). The VEGFR-3 tyrosine kinase receptor is expressed in the normal lymphatic endothelium and is upregulated in many types of vascular tumors, including Kaposi's sarcomas. Jussila, et al., Cancer Res 58, 1955-1604 (1998); Partanen, et al., Cancer 86:2406-2412 (1999). Absence or dysfunction of lymphatic vessels which can result from an infection, surgery, radiotherapy or from a genetic defect, causes lymphedema, which is characterized by a chronic accumulation of protein-rich fluid in the tissues that leads to swelling. The importance of VEGFR-3 signaling for lymphangiogenesis was revealed in the genetics of familial lymphedema, a disease characterized by a hypoplasia of cutaneous lymphatic vessels, which leads to a disfiguring and disabling swelling of the extremities. Witte, et al., Regulation of Angiogenesis (eds. Goldber, I. D. & Rosen, E. M.) 65-112 (Birkauser, Basel, Switzerland, 1997); Rockson, S. G, Am. J. Med. 110, 288-295 (2001). Some members of families with lymphoedema are heterozygous for missense mutations of the VEGFR3 exons encoding the tyrosine kinase domain, which results in an inactive receptor protein. Karkkainen, et al., Nature Genet. 25:153-159 (2000); Irrthum, et al., Am. J. Hum. Genet. 67:295-301 (2000).

There is a need in the art for information on the transcriptional program which controls the diversity of endothelial cells, and into the mechanisms of angiogenesis and lymphangiogenesis. There is also a need in the art for new vascular markers, which may be used as valuable targets in the study of a number of diseases involving the lymphatic vessels, including tumor metastasis.

SUMMARY OF THE INVENTION[TO BE REVISED UPON FINALIZATION OF CLAIMS]

The compositions of the present invention include isolated polynucleotides, in particular, lymphatic endothelial genes, polypeptides, isolated polypeptides encoded by these polynucleotides, recombinant DNA molecules, cloned genes or degenerate variants thereof, especially naturally occurring variants such as allelic variants, and antibodies that specifically recognize one or more epitopes present on such polypeptides.

The compositions of the present invention additionally include vectors, including expression vectors, containing the polynucleotides of the invention, cells genetically engineered to contain such polynucleotides and cells genetically engineered to express such polynucleotides.

In selected embodiments, such isolated polynucleotides of the invention represent a polynucleotide comprising a nucleotide sequence set forth in the sequence listing, e.g., any of SEQ ID NOS:1-30.

The polynucleotides of the present invention also include, but are not limited to, a polynucleotide that hybridizes to the complement of the nucleotide sequence of SEQ ID NOS:1-30 under highly stringent hybridization conditions; a polynucleotide that hybridizes to the complement of the nucleotide sequence of SEQ ID NOS:1-30 under moderately stringent hybridization conditions; a polynucleotide which is an allelic variant of any polynucleotide recited above; a polynucleotide which encodes a species homologue of any of the proteins recited above; of a polynucleotide that encodes a polypeptide comprising a specific domain or truncation of the polypeptide encoded by any one of SEQ ID NOS:1-30. Exemplary high stringency hybridization conditions are hybridization at 42° C. for 20 hours in a solution containing 50% formamide, 5×SSPE, 5× Denhardt's solution, 0.1% SDS and 0.1 mg/ml denatured salmon sperm DNA, with a wash in 1×SSC, 0.1% SDS for 30 minutes at 65° C.

Another aspect of the invention is drawn to LEC and BEC polypeptides, including polypeptides encoded by the polynucleotides described above. In some embodiments, the polypeptides are the mature forms of the polypeptides of the invention. Expressly contemplated is a purified and isolated polypeptide comprising an amino acid sequence selected from the group consisting of SEQ ID NOS: 31-44, 46, 48, 50, 52, 81, 187, 207, 211, 221, 235, 241, 293, and 391; and a purified and isolated polypeptide comprising an amino acid sequence selected from the group consisting of: (a) SEQ ID NOS: 31-34, 46, 48, 207, 676, 859, and 861; and (b) an extracellular domain fragment of at least 10 amino acids of an amino acid sequence of (a). Further, this aspect of the invention includes a purified and isolated, soluble polypeptide as described immediately above, comprising an extracellular domain fragment of an amino acid sequence selected from the group consisting of: SEQ ID NOS: 31-34, 46, 48, 207, 676, 859, and 861, wherein the polypeptide lacks any transmembrane domain. Such a polypeptide may further lack any intracellular domain. Also, the invention contemplates a fusion protein comprising a polypeptide as described above fused to an immunoglobulin fragment comprising an immunoglobulin constant region.

In a related aspect, the invention provides a composition comprising a polypeptide or protein as described above and a pharmaceutically acceptable diluent, carrier or adjuvant; Polypeptide compositions of the invention may comprise an acceptable carrier, such as a hydrophilic, e.g., pharmaceutically acceptable, carrier. Further provided is a kit comprising such a composition and a protocol for administering the pharmaceutical composition to a mammalian subject to modulate the lymphatic system in the subject. The invention also provides an antibody that specifically binds to a polypeptide as described above, and that antibody is humanized in some embodiments. Still further, the invention provides a protein comprising an antigen binding domain of an antibody that specifically binds to a polypeptide as described hereinabove, wherein the protein specifically binds to the polypeptide.

The invention also relates to methods for producing a polypeptide comprising growing a culture of the cells of the invention in a suitable culture medium, and purifying the protein from the culture or from an extract of the cells. In particular, the invention contemplates a method for producing a LEC polypeptide comprising steps of growing a host cell transformed or transfected with an expression vector as described herein under conditions in which the cell expresses the polypeptide encoded by the polynucleotide.

Methods of identifying the products and compositions described herein are also provided by the invention. In particular, the invention provides a method of identifying a LEC nucleic acid comprising: (a) contacting a biological sample containing a candidate LEC nucleic acid with a polynucleotide comprising a fragment of at least 14 contiguous nucleotides of a sequence selected from the group consisting of SEQ ID NOS:1-30, 45, 47, 49, 51, 82, 93, 111, 188, 208, 212, 236, 242, 294, and 392, or a complement thereof, under the following stringent hybridization conditions: (i) hybridization at 42° C. for 20 hours in a solution containing 50% formamide, 5×SSPE, 5× Denhardt's solution, 0.1% SDS and 0.1 mg/ml denatured salmon sperm DNA, and (ii) washing for 30 minutes at 65° C. in 1×SSC, 0.1% SDS; and (b) detecting hybridization of the candidate LEC nucleic acid and the polynucleotide, thereby identifying a LEC nucleic acid.

The invention also provides a method of identifying a LEC protein comprising: (a) contacting a biological sample containing a candidate LEC protein with a LEC protein binding partner selected from the group consisting of an antibody as described herein or a protein or polypeptide as described herein, under conditions suitable for binding therebetween; and (b) detecting binding between the candidate LEC protein and the LEC binding partner, thereby identifying a LEC protein.

Another related aspect of the invention is a method of identifying a LEC comprising: (a) contacting a biological sample comprising cells with a LEC binding partner under conditions suitable for binding therebetween, wherein the LEC binding partner comprises an antibody that binds to a polypeptide comprising a sequence selected from the group consisting of SEQ ID NOS:31-34, 46, 48, 207, 676, 859, and 861, or comprises an antigen binding fragment of the antibody; and (b) identifying a LEC by detecting binding between a cell and the LEC binding partner, where binding of the LEC binding partner to the cell identifies a LEC.

Polynucleotides according to the invention have numerous applications in a variety of techniques known to those skilled in the art of molecular biology. These techniques include use as hybridization probes, use as primers for PCR, use for chromosome and gene mapping, use in the recombinant production of protein, and use in generation of anti-sense DNA or RNA, their chemical analogs and the like. For example, when the expression of an mRNA is largely restricted to a particular cell or tissue type, such as a lymphatic endothelial cell, polynucleotides of the invention can be used as hybridization probes to detect the presence of the particular cell or tissue mRNA in a sample using, e.g., in situ hybridization.

In another aspect, the invention provides a composition comprising an isolated polynucleotide that comprises a nucleotide sequence that encodes a polypeptide comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 31-44, 46, 48, 50, 52, 81, 187, 207, 211, 221, 235, 241, 293, and 391; and a pharmaceutically acceptable diluent, carrier or adjuvant. In some embodiments, the composition comprises a polynucleotide that comprises a nucleotide sequence selected from the group consisting of SEQ ID NOS: 14-30, 45, 47, 49, 51, 82, 93, 111, 188, 208, 212, 222, 236, 242, 294, and 392, or a fragment thereof that encodes the polypeptide.

Still another aspect of the invention is an expression vector comprising an expression control sequence operably linked to a polynucleotide that comprises a nucleotide sequence that encodes a polypeptide comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 31-44, 46, 48, 50, 52, 81, 187, 207, 211, 221, 235, 241, 293, and 391. In some embodiments, the expression vector is a replication-deficient adenoviral or adeno-associated viral vector containing the polynucleotide. A related aspect of the invention is a composition comprising an expression vector as described above and a pharmaceutically acceptable diluent, carrier, or adjuvant. Further, the invention provides a kit comprising the composition containing either the above-described polynucleotide or vector and a pharmaceutically acceptable diluent, carrier or adjuvant, packaged with a protocol for administering the composition to a mammalian subject to modulate the lymphatic system in the subject.

The invention further provides a host cell transformed or transfected with an expression vector as described above.

The polypeptides according to the invention can be used in a variety of conventional procedures and methods that are currently applied to other proteins. In addition, a polypeptide of the invention can be used to generate an antibody that specifically binds the polypeptide.

In one aspect of the invention, a method is provided for differentially modulating the growth or differentiation of blood endothelial cells (BEC) or lymphatic endothelial cells (LEC), comprising contacting endothelial cells with a composition comprising an agent that differentially modulates blood or lymphatic endothelial cells, said agent selected from the group consisting of: (a) a polypeptide that comprises an amino acid sequence of a BEC polypeptide or a LEC polypeptide, or an active fragment of the polypeptide; (b) a polynucleotide that comprises a nucleotide sequence that encodes a polypeptide according to (a); (c) an antibody that specifically binds to a polypeptide according to (a); (d) a polypeptide comprising a fragment of the antibody of (c), wherein the fragment and the antibody bind to the polypeptide; (e) an antisense nucleic acid to a human gene or mRNA encoding the polypeptide of (a); (f) an interfering RNA (RNAi) to a human gene or mRNA encoding the polypeptide of (a). The method may involve endothelial cell contact with the composition ex vivo or in vivo. The composition may comprise a pharmaceutically acceptable diluent, adjuvant, or carrier, and the contacting step may comprise administering the composition to a mammalian subject to differentially modulate BECs or LECs in the mammalian subject.

Further, the method may comprise identifying a human subject with a disorder characterized by hyperproliferation of LECs; and administering to the human subject the composition, wherein the agent differentially inhibits LEC growth compared to BEC growth; alternatively the method may comprise identifying a human subject with a disorder characterized by hyperproliferation of LECs; screening LECs of the subject to identify overexpression of a polypeptide set forth in Table 3; and administering to the human subject the composition, wherein the agent differentially inhibits LEC growth compared to BEC growth by inhibiting expression of the polypeptide identified by the screening step.

This aspect of the invention also contemplates a method of modulating the growth of lymphatic endothelial cells in a human subject, comprising steps of identifying a human subject with a hypoproliferative lymphatic disorder; screening the subject to identify underexpression or underactivity of a LEC polypeptide set forth in Table 3, wherein the protein is not set forth in Table 1 or 2; administering to the human subject the composition, wherein the agent comprises the LEC polypeptide (a) identified by the screening step or an active fragment of the polypeptide, or comprises the polynucleotide (b) that comprises a nucleotide sequence that encodes the polypeptide.

A related aspect of the invention is drawn to a use of an agent for the manufacture of a medicament for the differential modulation of blood vessel endothelial cell (BEC) or lymphatic vessel endothelial cell (LEC) growth or differentiation, the agent selected from the group consisting of: (a) a polypeptide that comprises an amino acid sequence of a BEC polypeptide or a LEC polypeptide, or an active fragment of the polypeptide; (b) a polynucleotide that comprises a nucleotide sequence that encodes a polypeptide according to (a); (c) an antibody that specifically binds to a polypeptide according to (a); (d) a polypeptide comprising a fragment of the antibody of (c), wherein the fragment and the antibody bind to the polypeptide; (e) an antisense nucleic acid to a human gene or mRNA encoding the polypeptide of (a); (f) an interfering RNA (RNAi) to a human gene or mRNA encoding the polypeptide of (a).

In another aspect, the invention provides a method of identifying compounds that modulate growth of endothelial cells, comprising culturing endothelial cells in the presence and absence of a compound; and measuring expression of at least one BEC or LEC gene in the cells, wherein the BEC or LEC gene is selected from the genes encoding polypeptides set forth in Tables 3 and 4, wherein a change in expression of at least one BEC gene in the presence compared to the absence of the compound identifies the compound as a modulator of BEC growth, and wherein a change in expression of at least one LEC gene in the presence compared to the absence of the compound identifies the compound as a modulator of LEC growth. The method may be used to screen for a compound that selectively modulates BEC or LEC growth or differentiation, wherein the measuring step comprises measuring expression of at least one BEC gene and at least one LEC gene in the cells, and wherein the method comprises screening for a compound that selectively modulates BEC or LEC growth or differentiation by selecting a compound that differentially modulates expression of the at least one BEC gene compared to expression of the at least one LEC gene.

Further, the invention comprehends a method or use according to the aspects of the invention described above, wherein the polypeptide is a LEC polypeptide selected from the LEC polypeptides set forth in Table 3, and the agent differentially modulates LEC growth or differentiation over BEC growth or differentiation. In some embodiments, the LEC polypeptide comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 81, 187, 207, 211, 221, 235, 241, 293, and 391; in other embodiments, the LEC polypeptide comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 31-34, 46, and 48. In these embodiments, an agent may be an antibody that specifically binds to a LEC polypeptide as described above, or a polypeptide fragment of such an antibody. Further, the agent may be an extracellular domain of a polypeptide described above, a polynucleotide encoding an extracellular domain, or an antisense molecule or nucleic acid. Alternatively, the polypeptide is a BEC polypeptide selected from the BEC polypeptides set forth in Table 4, and the agent differentially modulates BEC growth or differentiation over LEC growth or differentiation. Preferably, the polypeptides are not set forth in Tables 1 or 2.

The methods of the present invention further relate to methods for detecting the presence of the polynucleotides or polypeptides of the invention in a sample. Such methods can, for example, be utilized as part of prognostic and diagnostic evaluation of disorders as recited above and for the identification of subjects exhibiting a predisposition to such conditions. Furthermore, the invention provides methods for evaluating the efficacy of drugs, and monitoring the progress of patients, involved in clinical trials for the treatment of disorders related to lymphatic endothelial cells.

The invention also provides methods for the identification of compounds that modulate the expression of the polynucleotides and/or polypeptides of the invention. Such methods can be utilized, for example, for the identification of compounds that can ameliorate symptoms of disorders related to expression of proteins encoded by any one of SEQ ID NOS:1-30 as recited above. Such methods can include, but are not limited to, assays for identifying compounds and other substances that interact with (e.g., bind to) the polypeptides of the invention.

Further, the invention provides a method of assaying for risk of developing hereditary lymphedema, comprising (a) assaying nucleic acid of a human subject for a mutation that correlates with a hereditary lymphedema phenotype and alters the encoded amino acid sequence of at least one gene allele of the human subject when compared to the amino acid sequence of the polypeptide encoded by a corresponding wild-type gene allele, wherein the wild-type polypeptide is a polypeptide identified in Table 3. Alternatively, a method of assaying for risk of developing hereditary lymphedema, comprises (a) assaying nucleic acid of a human subject for a mutation that correlates with a hereditary lymphedema phenotype and alters the encoded amino acid sequence of at least one gene allele of the human subject when compared to the amino acid sequence of the polypeptide encoded by a corresponding wild-type gene allele, wherein the wild-type polypeptide comprises an amino acid sequence selected from the group consisting of SEQ D NOS: 31-44, 46, 48, 52, 54, 207, 676, 859, and 861; (b) correlating the presence or absence of the mutation in the nucleic acid to a risk of developing hereditary lymphedema, wherein the presence of the mutation in the nucleic acid correlates with an increased risk of developing hereditary lymphedema, and wherein the absence of the mutation in the nucleic acid correlates with no increased risk of developing hereditary lymphedema.

In another method of assaying for risk of developing hereditary lymphedema, the steps comprise (a) assaying nucleic acid of a human subject for a mutation that alters the encoded amino acid sequence of at least one transcription factor allele of the human subject and alters transcription modulation activity of the transcription factor polypeptide encoded by the allele, when compared to the transcription modulation activity of a transcription factor polypeptide encoded by a wild-type allele, wherein the wild-type transcription factor polypeptide comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 81, SEQ ID NO: 211, SEQ ID NO: 241, and transcription factors encoded by sequences in Table 5; and (b) correlating the presence or absence of the mutation in the nucleic acid to a risk of developing hereditary lymphedema, wherein the presence of the mutation in the nucleic acid correlates with an increased risk of developing hereditary lymphedema, and wherein the absence of the mutation in the nucleic acid correlates with no increased risk of developing hereditary lymphedema. In this method, the wild-type transcription factor allele may comprise the Sox18 amino acid sequence set forth as SEQ ID NO:54. In some embodiments of this method, the assaying identifies a mutation altering a transactivating or DNA binding domain amino acid sequence of the protein encoded by the Sox18 allele; in some other embodiments of the method, the mutation reduces transcriptional activation of a SOX18-responsive gene compared to transcriptional activation of the gene by wild-type SOX18.

In a related aspect, the invention provides a method of assaying for risk of developing hereditary lymphedema, comprising (a) assaying nucleic acid of a human subject for a mutation that alters the encoded amino acid sequence of at least one LEC gene allele of the human subject and alters the binding affinity of the adhesion polypeptide encoded by the LEC gene allele, when compared to the binding affinity of an adhesion polypeptide encoded by a wild-type allele, wherein the wild-type adhesion polypeptide comprises an amino acid sequence selected from the group consisting of SEQ ID NOS:31-34, 46, 207, 676, 859, and 861; and (b) correlating the presence or absence of the mutation in the nucleic acid to a risk of developing hereditary lymphedema, wherein the presence of the mutation in the nucleic acid correlates with an increased risk of developing hereditary lymphedema, and wherein the absence of the mutation in the nucleic acid correlates with no increased risk of developing hereditary lymphedema. In some embodiments of this method, the at least one gene corresponds to the human Sox18 gene that encodes the amino acid sequence set forth in SEQ ID NO: 54.

In the methods of assaying for risk of developing hereditary lymphedema according to the invention, the assaying may identify the presence of the mutation, and the correlating step may identify the increased risk of the patient developing hereditary lymphedema.

A related method according to the invention is a method of screening a human subject for an increased risk of developing hereditary lymphedema comprising assaying nucleic acid of a human subject for a mutation that alters the encoded amino acid sequence of at least one polypeptide comprising an amino acid sequence of Table 3. In some embodiments of this method, the polypeptide comprises an amino acid sequence selected from the group consisting of SEQ ID NOS: 31-44, 46, 48, 50, 52, and 54, 207, 676, 859, and 861 in a manner that correlates with the risk of developing hereditary lymphedema, and it is expressly contemplated that the polypeptide may comprise the SOX18 amino acid sequence set forth in SEQ ID NO: 54.

A related aspect of the invention is drawn to methods of assaying or screening for risk of developing hereditary lymphedema as described above, wherein the method comprises at least one procedure selected from the group consisting of: (a) determining a nucleotide sequence of at least one codon of at least one polynucleotide of the human subject; (b) performing a hybridization assay to determine whether nucleic acid from the human subject has a nucleotide sequence identical to or different from one or more reference sequences; (c) performing a polynucleotide migration assay to determine whether nucleic acid from the human subject has a nucleotide sequence identical to or different from one or more reference sequences; and (d) performing a restriction endonuclease digestion to determine whether nucleic acid from the human subject has a nucleotide sequence identical to or different from one or more reference sequences.

A related aspect of the invention provides methods of assaying or screening for risk of developing hereditary lymphedema as described above, wherein the method comprises: performing a polymerase chain reaction (PCR) to amplify nucleic acid comprising the coding sequence of the LEC polynucleotide, and determining nucleotide sequence of the amplified nucleic acid.

Further provided by the invention is a method of screening for a hereditary lymphedema genotype in a human subject, comprising: (a) providing a biological sample comprising nucleic acid from said subject, and (b) analyzing the nucleic acid for the presence of a mutation altering the encoded amino acid sequence of the at least one allele of at least one gene in the human subject relative to a human gene encoding an amino acid sequence selected from the group consisting of SEQ ID NOs: 31-44, 46, 48, 50, 52, 54, 207, 676, 859, and 861, wherein the presence of a mutation altering the encoded amino acid sequence in the human subject in a manner that correlates with lymphedema in human subjects identifies a hereditary lymphedema genotype. In some embodiments of this method, the biological sample is a cell sample. In other embodiments of this method, the analyzing comprises sequencing a portion of the nucleic acid. In still further embodiments of this method, the human subject has a hereditary lymphedema genotype identified by the method of screening.

Another aspect of the invention provides a method of inhibiting lymphangiogenesis comprising administering to a subject an inhibitor of a LEC transmembrane polypeptide, wherein the LEC transmembrane polypeptide comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 31-34, 46 48, 207, 676, 859, and 861, and wherein the inhibitor is selected from the group consisting of (a) a soluble extracellular domain fragment of the LEC transmembrane polypeptide; (b) an antibody that binds to the extracellular domain of the LEC transmembrane polypeptide; (c) a polypeptide comprising an antigen binding domain of the antibody according to (b); and (d) an antisense nucleic acid complementary to the nucleic acid encoding the LEC transmembrane polypeptide or its complement. In some embodiments of the method, the inhibitor is a polypeptide comprising an extracellular domain fragment of an LEC polypeptide, wherein the sequence of the extracellular domain is selected from the group consisting of amino acids 1-152 of SEQ ID NO:31, amino acids 1-695 of SEQ ID NO:32 and amino acids 1-248 of SEQ ID NO:33. In some embodiments of the method, the subject is a human containing a tumor.

In a related aspect, the invention provides a method for modulating lymphangiogenesis in a mammalian subject comprising: administering to a mammalian subject in need of modulation of lymphangiogenesis an antisense molecule to a LEC polynucleotide, in an amount effective to inhibit transcription or translation of the polypeptide encoded by the LEC polynucleotide, wherein the LEC polynucleotide comprises a nucleotide sequence selected from the group consisting of SEQ ID NOS: 14-30, 45, 47, 49, AND 51, 208, 677, 860, and 862.

The methods of the invention also include methods for the treatment of disorders related to lymphatic endothelial cells as recited above which may involve the administration of such compounds to individuals exhibiting symptoms or tendencies related to such disorders.

In another aspect, the invention provides a method of treating hereditary lymphedema, comprising: (a) identifying a human subject with hereditary lymphedema and with a mutation that alters the encoded amino acid sequence of at least one polypeptide of the human subject, relative to the amino acid sequence of a polypeptide comprising an amino acid sequence selected from the group consisting of SEQ ID NOS: 31-44, 46, 48, 50, 52, 54, 207, 676, 859, and 861; and (b) administering to the subject a lymphatic growth factor selected from the group consisting of a VEGF-C polynucleotide, a VEGF-C polypeptide, a VEGF-D polynucleotide, and a VEGF-D polypeptide.

The invention also provides a method of treating hereditary lymphedema comprising: identifying a human subject with lymphedema and with a mutation in at least one allele of a gene encoding a LEC protein identified in Table 3, wherein the mutation correlates with lymphedema in human subjects, and with the proviso that the LEC protein is not VEGFR-3; and administering to the subject a composition comprising a lymphatic growth agent selected from the group consisting of VEGF-C polypeptides, VEGF-D polypeptides, VEGF-C polynucleotides, and VEGF-D polynucleotides. The invention also comprehends use of a lymphatic growth agent selected from the group consisting of VEGF-C polypeptides, VEGF-D polypeptides, VEGF-C polynucleotides, and VEGF-D polynucleotides in the manufacture of a medicament for the treatment of hereditary lymphedema resulting from a mutation in a LEC gene identified in Table 3, with the proviso that the gene is not VEGFR-3.

In addition, the invention encompasses methods for treating such diseases or disorders by administering compounds and other substances that modulate the overall activity of the target gene products. Compounds and other substances can effect such modulation either at the level of target gene expression or target protein activity. These treatment methods include the administration of a polypeptide or a polynucleotide according to the invention to an endothelial cell, e.g., a LEC and/or a BEC, or to an organism such as a human patient. An exemplary method according to this aspect of the invention is the administration of a therapeutic selected from the group consisting of an antisense polynucleotide capable of modulating the expression of at least one polynucleotide according to the invention, a polypeptide according to the invention, a polynucleotide according to the invention, an antibody or antibody fragment specifically recognizing a polypeptide according to the invention, a VEGF-C polynucleotide, a VEGF-C polypeptide, a VEGF-D polynucleotide, a VEGF-D polypeptide and a soluble VEGFR-3 polypeptide.

In another aspect, the invention provides a method of screening for an endothelial cell disorder or predisposition to the disorder, comprising obtaining a biological sample containing endothelial cell mRNA from a human subject; and measuring expression of a BEC or LEC gene from the amount of mRNA in the sample transcribed from the gene, wherein the BEC or LEC gene encodes a polypeptide identified in Table 3 or 4.

The invention relates to a method of inhibiting the growth of a lymphatic endothelial cell, the method comprising contacting the cell with a composition comprising at least one antibody conjugated to an agent capable of inhibiting the growth, wherein the agent is selected from the group consisting of a cytotoxic agent and a cytostatic agent, and wherein the antibody specifically binds to a polypeptide encoded by a polynucleotide comprising a sequence selected from the group consisting of SEQ ID NOS:14-17, 45, 47, 860 and 862. In specific embodiments of this method, the polypeptide comprises an amino acid sequence selected from the group consisting of SEQ ED NOS:31-34, 46, 48, 859 and 861.

The invention further relates to methods of detecting a lymphatic endothelial cell, the method comprising contacting the cell with a composition comprising at least one antibody conjugated to a detectable agent, such as a fluorescent molecule or a radiolabeled molecule. In specific embodiments, the antibody specifically binds to a polypeptide encoded by a polynucleotide comprising a sequence selected from the group consisting of SEQ ID NOS: 14-17, 45, 47, 860 and 862. In further specific embodiments of this method, the polypeptide comprises an amino acid sequence selected from the group consisting of SEQ ID NOS: 31-34, 46, 48, 859 and 861.

The invention still further relates to methods of isolating a lymphatic endothelial cell, comprising contacting the cell with a solid matrix comprising at least one antibody capable of binding to a transmembrane protein in the cell membrane of the cell, and isolating cells specifically bound to the antibody matrix. In specific embodiments, the antibody specifically binds to a polypeptide encoded by a polynucleotide comprising a sequence selected from the group consisting of SEQ ID NOS:14-17, 45, 47, 860 and 862. In further specific embodiments of this method, the polypeptide comprises an amino acid sequence selected from the group consisting of SEQ ID NOS:31-34, 46, 48, 859 and 861.

The invention also relates to the administration of an agonist or antagonist to a lymphatic endothelial cell, comprising selecting an antibody, a peptide or a small molecular weight compound that is capable of specifically binding to a lymphatic endothelial cell-specific protein, wherein the antibody, peptide or small molecular weight compound is an agonist or antagonist for a growth factor receptor, a cytokine receptor, a chemokine receptor, or a hemopoietic receptor, and contacting the antibody, peptide or small molecular weight compound with the lymphatic endothelial cell in need of growth stimulation or inhibition. In specific embodiments, such lymphatic endothelial cells are involved in lymphedema, lymphangioma, lymphangiomyeloma, lymphangiomatosis, lymphangiectasis, lymphosarcoma, and lymphangioscierosis.

The invention also relates to the administration of a cytotoxic or cytostatic drug to a lymphatic endothelial cell, comprising selecting an antibody, a peptide or a small molecular weight compound that is capable of specifically binding to a lymphatic endothelial cell-specific protein, wherein the antibody, peptide or small molecular weight compound is complexed to the cytotoxic or cytostatic drug. In specific embodiments, administration of such complexes is useful in the treatment of malignant tumor diseases prone to metastatic spread through the lymphatic system.

The invention also provides a method of monitoring the efficacy or toxicity of a drug on endothelial cells, comprising steps of measuring expression of at least one BEC or LEC gene in endothelial cells of a mammalian subject before and after administering a drug to the subject, wherein the at least one BEC or LEC gene encodes a polypeptide set forth in Table 3 or Table 4, and wherein changes in expression of the BEC or LEC gene correlates with efficacy or toxicity of the drug on endothelial cells.

The invention relates to a lymphatic endothelial cell marker protein comprising a polypeptide encoded by a polynucleotide selected from the group consisting of SEQ ID NOS:14-17; and a polynucleotide hybridizable under stringent conditions with any one of SEQ ID NOS:14-17. In specific embodiments, the lymphatic endothelial cell marker protein comprises a polypeptide selected from the group consisting of SEQ ID NOS:3 1-34.

The invention also relates to an antibody capable of specifically binding to a lymphatic endothelial cell marker protein comprising a polypeptide selected from the group consisting of SEQ ID NOS:31-34.

The invention further relates to a method of detecting a lymphatic endothelial cell, comprising contacting said cell with the antibody wherein said antibody is detectably labeled.

The invention still further relates to a method of inhibiting at least one biological activity of a lymphatic endothelial cell, comprising contacting the cell with an agent capable of binding to at least one polypeptide encoded by any one of SEQ ID NOS:14-17, 45, 47, 860 and 862, wherein the activity of the polypeptide is reduced relative to the activity of a polypeptide that is not contacted with the agent.

The invention also relates to a method of inhibiting the growth of a lymphatic endothelial cell, the method comprising contacting the cell with an antisense oligonucleotide capable of specifically binding to at least one polynucleotide selected from the group consisting of SEQ ID NOS:1-30, 45, 47, 860 and 862. In a specific embodiment, the antisense oligonucleotide consists essentially of about 12 to about 25 contiguous nucleotides of any one of SEQ ID NOS: 1-30, 45, 47, 860 and 862.

Additional features and variations of the invention will be apparent to those skilled in the art from the entirety of this application, and all such features are intended as aspects of the invention.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1: Examples of differentially expressed genes in LECs and BECs. Northern blotting and hybridization for the indicated transcripts. Equal loading was verified by probing with GAPDH. For the microarray analyses, RNA was extracted from LECs which were cultured in the presence of VEGF-C (LEC/+C). When validating the array results, RNA was extracted as a control also from cultures of LECs in which VEGF-C was not added (LEC/−C).

FIG. 2: Cytoskeletal structures, cadherin complexes and integrin α9 expression in BECs and LECs. Mixed cultures of LEC and BEC were double-stained for N-cadherin (a), VE-cadherin (c), β-catenin (e), plakoglobin (g), F-actin (i) and integrin α9 (k), and for the LEC-specific marker podoplanin (green; b, d, f, h, j, l). Expression of integrin α9 in the lymphatic (arrow) but not in blood vessel endothelia (arrowhead). Adjacent sections of human skin were stained with antibodies against integrin α9 (m), VEGFR-3 (n) or blood vessel endothelial antigen PAL-E (o).

DETAILED DESCRIPTION OF THE INVENTION

A major role of the lymphatic vasculature is to remove an excess of the protein-rich interstitial fluid that continuously escapes from the blood capillaries, and to return it to the blood circulation (Witte, M. H., et al., Microsc. Res. Tech. 55:122-145. 2001; Karpanen, T., et al., J. Exp. Med. 194:F37-F42. 2001; Karkkainen, M. J., et al., Trends Mol. Med. 7:18-22. 2001). In addition, the lymphatic system provides constant immune surveillance by filtering lymph and its antigens through the chain of lymph nodes, and also serves as one of the major routes for absorption of lipids from the gut. It has been known for a long time-that in many types of cancer the lymphatic vessels provide a major pathway for tumor metastasis, and regional lymph node dissemination correlates with the progression of the disease. Hereditary lymphedema, post-surgical secondary lymphedema and lymphatic obstruction in filariasis, are all characterized by disabling and disfiguring swelling of the affected areas, linked to the insufficiency or obstruction of the lymphatics. Witte, M. J., et al., Microsc. Res. Tech 55:122-145 (2001).

In spite of the importance of lymphatic vessels in medicine, the cell biology of this part of the vascular system has received little attention until recently. Studies during the past four years have uncovered the existence of the lymphatic specific vascular endothelial growth factors VEGF-C and VEGF-D, which serve as ligands for the receptor tyrosine kinase VEGFR-3, and demonstrated their importance for the normal development of the lymphatic vessels (See, Jeltsch, M., et al., Science 276:1423-1425 (1997); Veikkola, T., et al., EMBO J. 20:1223-1231 (2001); Mäkinen, T., et al., Nat. Med. 7:199-205 (2001)). These molecules also appear to be involved in the development of lymphedema and lymphatic metastasis (Karpanen, T., et al., J. Exp. Med. 194:F37-F42 (2001); Karkkainen, M. J., et al., Trends Mol. Med. 7:18-22. 2001).

The growth factor Vascular Endothelial Growth Factor C (VEGF-C), as well as native human, non-human mammalian, and avian polynucleotide sequences encoding VEGF-C, and VEGF-C variants and analogs, have been described in detail in International Patent Application Number PCT/US98/01973, filed Feb. 2, 1998 and published on Aug. 6, 1998 as International Publication Number WO 98/33917; in Joukov et al., J. Biol. Chem., 273(12): 6599-6602 (1998); and in Joukov et al., EMBO J., 16(13): 3898-3911 (1997), all of which are incorporated herein by reference in their entirety. As explained therein in detail, human VEGF-C (SEQ ID NO: 863) is initially produced in human cells as a prepro-VEGF-C polypeptide of 419 amino acids. A cDNA encoding human VEGF-C (SEQ ID NO: 864) has been deposited with the American Type Culture Collection (ATCC), 10801 University Blvd., Manassas, Va. 20110-2209 (USA), pursuant to the provisions of the Budapest Treaty (Deposit date of 24 Jul. 1995 and ATCC Accession Number 97231). VEGF-C sequences from other species also have been reported. See Genbank Accession Nos. MMU73620 (Mus musculus); and CCY15837 (Coturnix coturnix) for example, incorporated herein by reference.

The prepro-VEGF-C polypeptide is processed in multiple stages to produce a mature and most active VEGF-C polypeptide of about 21-23 kD, as assessed by SDS-PAGE under reducing conditions (SEQ ID NO: 863). Such processing includes cleavage of a signal peptide (residues 1-31); cleavage of a carboxyl-terminal peptide (corresponding approximately to amino acids 228-419 and having a pattern of spaced Cysteine residues reminiscent of a Balbiani ring 3 protein (BR3P) sequence [Dignam et al., Gene, 88:133-40 (1990); Paulsson et al., J. Mol. Biol., 211:331-49 (1990)]) to produce a partially-processed form of about 29 kD; and cleavage (apparently extracellularly) of an amino-terminal peptide (corresponding approximately to amino acids 32-103) to produced a fully-processed mature form of about 21-23 kD. Experimental evidence demonstrates that partially-processed forms of VEGF-C (e.g., the 29 kD form) are able to bind VEGFR-3 (Flt4 receptor), whereas high affinity binding to VEGFR-2 occurs only with the fully processed forms of VEGF-C. It appears that VEGF-C polypeptides naturally associate as non-disulfide linked dimers.

It has been demonstrated that amino acids 103-227 of VEGF-C are not all critical for maintaining VEGF-C functions. A polypeptide consisting of amino acids 113-213 (and lacking residues 103-112 and 214-227) retains the ability to bind and stimulate VEGF-C receptors, and it is expected that a polypeptide spanning from about residue 131 to about residue 211 will retain VEGF-C biological activity. The Cysteine residue at position 156 has been shown to be important for VEGFR-2 binding ability. However, VEGF-C ΔC₁₅₆ polypeptides (i.e., analogs that lack this Cysteine due to deletion or substitution) remain potent activators of VEGFR-3. The Cysteine at position 165 of VEGF-C polypeptide is essential for binding either receptor, whereas analogs lacking the Cysteine at positions 83 or 137 compete with native VEGF-C for binding with both receptors and stimulate both receptors.

VEGF-D is structurally and functionally most closely related to VEGF-C [see U.S. Pat. No. 6,235,713 and International Patent Publ. No. WO 98/07832, incorporated herein by reference]. See SEQ ID NO: 866 for the polynucleotide sequence of VEGF-D; the encoded amino acid sequence is set forth in SEQ ID NO: 865. Like VEGF-C, VEGF-D is initially expressed as a prepro-peptide that undergoes N-terminal and C-terminal proteolytic processing, and forms non-covalently linked dimers. VEGF-D stimulates mitogenic responses in endothelial cells in vitro. During embryogenesis, VEGF-D is expressed in a complex temporal and spatial pattern, and its expression persists in the heart, lung, and skeletal muscles in adults. Isolation of a biologically active fragment of VEGF-D designated VEGF-DΔNΔC, is described in International Patent Publication No. WO 98/07832, incorporated herein by reference. VEGF-DΔNΔC consists of amino acid residues 93 to 201 of VEGF-D (SEQ ID NO: 26) optionally linked to the affinity tag peptide FLAG®, or other sequences.

The prepro-VEGF-D polypeptide has a putative signal peptide of 21 amino acids and is apparently proteolytically processed in a manner analogous to the processing of prepro-VEGF-C. A “recombinantly matured” VEGF-D lacking residues 1-92 and 202-354 retains the ability to activate receptors VEGFR-2 and VEGFR-3, and appears to associate as non-covalently linked dimers. Thus, preferred VEGF-D polynucleotides include those polynucleotides that comprise a nucleotide sequence encoding amino acids 93-201. The guidance provided above for introducing function-preserving modifications into VEGF-C polypeptides is also suitable for introducing function-preserving modifications into VEGF-D polypeptides. As another aspect of the invention, practice of the invention methods is contemplated wherein VEGF-D polypeptides are employed in lieu of VEGF-C polypeptides.

When compared with the blood vascular endothelium, the lymphatic endothelium exhibits specific morphological and molecular characteristics. For example, the lymphatic capillaries are larger than blood capillaries, they have an irregular or collapsed lumen with no red blood cells, a discontinuous basal lamina, overlapping intercellular junctional complexes and anchoring filaments that connect the lymphatic endothelial cells to the extracellular matrix (Witte, M. H., et al., Microsc. Res. Tech. 55:122-145 (2001)). Unlike the blood capillaries, the lymphatic capillaries lack pericyte coverage. At the molecular level several lymphatic specific markers have been identified, including VEGFR-3, the Prox-1 transcription factor, the hyaluronan receptor LYVE-1, the membrane mucoprotein podoplanin, the beta-chemokine receptor D6, the cytoskeletal proteins desmoplakin I and II and the macrophage mannose receptor I (Wigle, J. T. & Oliver, G, Cell 98:769-778 (1999); Banedji, S., et al., J. Cell Biol. 144:789-801 (1999): Breiteneder-Geleff, S., et al., Am. J. Pathol. 154:385-394 (1999): Nibbs, R. J., et al., Am. J. Pathol. 158:867-877 (2001); Ebata, N., et al., Microvasc. Res. 61:40-48. (2001); Irjala, H., et al., J. Exp. Med. 194:1033-1041 (2001)). The present invention relates to the genetic identity of lymphatic capillary endothelial cells versus blood vascular endothelial cells using a gene profiling approach.

“Stringent hybridization conditions” or “stringent conditions” refer to conditions under which a nucleic acid such as an oligonucleotide will specifically hybridize to its target sequence. Stringent conditions are sequence-dependent and will be different in different circumstances. Longer nucleic acids hybridize specifically at higher temperatures than shorter sequences. Generally, stringent conditions are selected to be about 5° C. lower than the thermal melting point (T_(m)) for the specific sequence at a defined ionic strength and pH. The T_(m) is the temperature (under defined ionic strength, pH and nucleic acid concentration conditions) at which 50% of the nucleic acids complementary to the target sequence hybridize to the target sequence at equilibrium. The term “complementary” refers to standard Watson-Crick base pairing between nucleotides of two nucleic acid molecules. Typically, stringent conditions will be those in which the salt concentration is less than about 1.0 M sodium ion, typically about 0.01 to 1.0 M sodium ion (or other salts) at pH 7.0 to 8.3 and at a temperature that is at least about 30° C. for short probes, primers or oligonucleotides (e.g., 10. to 50 nucleotides) and at least about 60° C. for longer probes, primers or oligonucleotides. Stringent conditions also can be achieved with the addition of destabilizing agents, such as formamide, as is known in the art Exemplary stringent hybridization conditions are hybridization at 42° C. for 20 hours in a solution containing 50% forrnamide, 5×SSPE, 5× Denhardt's solution, 0.1% SDS and 0.1 mg/ml denatured salmon sperm DNA, with a wash in 1×SSC, 0.1% SDS for 30 minutes at 65° C.

According to the invention, distinct gene expression profiles for blood vascular and lymphatic endothelial cells have been discovered. These results provide new insights into the phenotypic diversity of endothelial cells and reveal new potential lymphatic endothelial molecules, some of which could provide important targets for the therapy of diseases characterized by abnormal angiogenesis or lymphangiogenesis.

Differences in the expression of genes encoding proteins involved in inflammatory processes were found, as well as in those mediating cell-cell and cell-matrix interactions. Furthermore, several previously unknown genes were identified in the context of endothelial cell biology, which were differentially expressed in the two cell lineages. Several of the genes were originally cloned from neural tissues, including genes involved in the uptake of synaptic macromolecules and in synapse formation and remodeling (neuronal pentraxins I and II (Kirkpatrick, L. L., et al., J. Biol. Chem.. 275:17786-17792. 2000), in the trafficking of synaptic vesicles (NAP-22 (Yamamoto, Y., et al., Neurosci. Lett. 224:127-130. 1997), piccolo (Fenster, S. D., et al., Neuron 25:203-214 (2000)) and in the axon growth and guidance (Nr-CAM (Grumet, M., Cell Tissue Res. 290:423-428 (1997), reelin (Rice, D. S. & Curran, T., Annu. Rev. Neurosci. 24:1005-1039 (2001)).

In addition, the LECs especially expressed a number of as yet uncharacterized genes, which were originally cloned and highly expressed in nervous tissues (KIAA genes (Kikuno, R., et al., Nucleic Acids Res. 30:166-168. 2002). The gene expression profiling data disclosed herein therefore support the view that the same molecular mechanisms that are involved in governing neural cell positioning, in guiding axonal growth cones to their specific targets and in synaptogenesis may also be commonly used in the development of the vascular system and in the establishment of BEC and LEC identity. Some other signaling molecules first described in the developing nervous system have already been implicated in the development of the vasculature and vice versa (Shima and Mailhos, Curr. Opin. Genet. Dev. 10:536-542 (2000); Oosthuyse, et al., Nat. Genet. 28:131-138 (2001); Sondell, et al., Eur. J. Neurosci. 12:4243-4254 (2000)).

In the LECs, expression of several genes previously shown to be expressed in smooth muscle cells (SMCs) and pericytes was observed, such as matrix Gla, a mineral binding extracellular matrix protein involved in the inhibition of vascular and tissue calcification (Luo, G, et al., Nature 386:78-81 (1997)), monoamine oxidase A, the main degradative enzyme of monoamine hormones and neurotransmitters (Rodriguez, M. J., et al., Cell Tissue Res. 304:215-220 (2001)), integrin α9 (Palmer, E. L., et al., J. Cell Biol. 123:1289-1297 (1993)) and apolipoprotein D (Hu, C. Y, et al., J. Neurocytol. 30:209-218 (2001)). Some similarity of gene expression patterns between LECs and SMCs could be related to the lack of SMC around lymphatic capillaries. Instead, LECs may carry out some SMC functions by themselves. For example, lymph flow is maintained due to the intrinsic contractility of the LECs (Witte, M. H., et al., Microsc. Res. Tech. 55:122-145 (2001)), reminiscent of the ability of vascular SMCs to contract.

Molecular discrimination of the lymphatic and blood vessels is essential in studies of diseases involving the blood and/or lymphatic vessels and in the targeted treatment of such diseases. To date, several lymphatic endothelial specific markers have been identified, but some of them are expressed only in a subset of the lymphatic vessels, while others also occur in some blood vessel endothelia or in other cell types and their expression patterns may change in pathological conditions (for example, VEGFR-3 (Valtola, R., et al., Am. J. Pathol. 154:1381-1390. 1999)). Identification of new vascular markers according to the invention should provide a more reliable analysis of the blood and lymphatic vessels in pathological situations and eventually better diagnosis and treatment. Furthermore, inhibition of the function of certain molecules involved in the regulation of angiogenesis and/or lymphangiogenesis is known to prevent tumor growth and metastasis, and stimulation of the growth of blood or lymphatic vessels has been shown to be beneficial in several pathological conditions. Thus the BEC and LEC specific molecular regulators identified according to the invention may provide new targets for the treatment of diseases characterized by abnormal angiogenesis and lymphangiogenesis.

Several of the new LEC genes encode transmembrane proteins that may be specific molecular markers for lymphatic endothelial cells (Table 6). These genes and encoded proteins are useful for targeted treatment of diseases that involve lymphatic vessels. They may also be useful for preparing antibodies, as antibodies against LEC-specific proteins can be used to discriminate between blood and lymphatic vessels in pathological and physiological situations. Antibodies may also be useful for the isolation of lymphatic endothelial cells. These proteins may also play a role in the regulation of lymphangiogenesis, and can provide new candidate genes for diseases that involve lymphatic vessels, such as lymphedema.

The lymphatic endothelial cell specific surface molecules can be used for molecular drug targeting with antibodies, peptides and small-molecular weight compounds, which can act as agonists or antagonists for growth factor receptor, cyto- and chemokine receptor, and hemopoietin receptor signaling, cell adhesion and cell interaction with extracellular matrix or with other cell surface molecules. Such molecules can also be used for targeting of cytotoxic or cytostatic drugs into the lymphatic endothelial cells and for the attachment of electron-dense, radio-opaque or radioactive markers for imaging of disease processes associated with the lymphatic vessels. Such diseases include lymphedema, lymphangioma, lymphangiomyoma, lymphangiomatosis, lymphangiectasis, lymphosarcoma and lymphangiosclerosis.

The lymphatic endothelial cell surface molecules may be used for targeting of gene therapy for example by antibody-coated liposomes (containing proteins or genes as cargo) or by viral transducing vectors such as adenoviruses, adeno-associated viruses or lentiviruses having modified capsid/envelope proteins. The manipulation of lymphatic endothelial cell specific molecules may be applicable to treatment of disease processes associated with tissue edema by increasing fluid transport across the lymphatic vessel wall for example by modulating endothelial cell-cell or cell-matrix interactions or via stimulating transendothelial transport. Targeting of the lymphatic endothelial cells for example with cytotoxic or cytostatic compounds is contemplated to be valuable in malignant tumor diseases prone to metastatic spread via the lymphatic system.

The lymphatic endothelial cell molecules may allow the improved in vitro growth of lymphatic endothelial cells as well as in vitro tissue engineering of lymphatic vessels for use in diseases where the lymphatics have been damaged, such as after surgery and in various forms of lymphedema. Ligands of the cell surface proteins may further be applied to coat various polymeric matrices for the adhesion of cells in, e.g., bioimplants.

The lymphatic endothelial-cell-specific molecules such as surface molecules can provide important tools for the modulation of inflammatory, autoimmune and infectious processes involving leukocyte migration and immune recognition as well as the stimulation of secondary immune responses. Such processes include the migration of antigen presenting cells into the lymphatic system including lymph nodes as well as fransendothelial cell trafficking of lymphocytes and other leukocyte subclasses and the homing, survival and function of the various classes of leukocytes.

These molecules may allow one to modulate the metabolism of fatty acids including fatty acid/chylomicron absorption from the gut and regulation of fat accumulation in adipose tissue in various organs such as in the subcutaneous tissue and in the arterial wall.

Lymphatic endothelial-cell-specific molecules may further allow one to modulate the metabolism of fatty acids including fatty acid/chylomicron absorption from the gut and regulation of fat accumulation in adipose tissue in various organs such as in the skin subcutaneous tissue and in the arterial wall.

The lymphatic-cell-specific transmembrane proteins are expected to function in cell adhesion (e.g., adhesion between lymphatic endothelial cell-lymphatic endothelial cell, lymphatic endothelial cell-smooth muscle cell, lymphatic endothelial cell-immune system cell such as lymphocyte or dendritic cell), cell-extracellular matrix contacts, or as receptors such as growth factor, cytokine, chemokine or microbial receptors or ion channels. The transmembrane proteins connect to intracellular molecules that can induce cell growth, cell migration, cell apoptosis, cell differentiation or cell adhesion or other cellular functions specific for endothelial cells such as expression of adhesion receptors for leukocytes, release of nitric oxide, antigoagulant proteins, uptake of fluid and proteins from surrounding tissues and fat from gut or adipose tissues. TM proteins with short intracellular domains can function as auxiliary receptors in complex with other TM proteins.

The transmembrane proteins and their intracellular binding partner molecules can be used as molecular markers for lymphatic endothelial cells in normal and disease conditions, and to discriminate between blood and lymphatic vessels in pathological and physiological situations.

Antibodies against lymphatic specific transmembrane proteins, as well as peptides and small molecular compounds binding to extracellular domains of lymphatic-specific TM proteins can be used for the attachment of electron-dense, radio-opaque or radioactive markers for imaging of disease processes associated with the lymphatic vessels. Such diseases include lymphedema, lymphangioma, lymphangiomyoma, lymphangiomatosis, lymphangiectasis, lymphosarcoma and lymphangiosclerosis. Similarly, the lymphatic vessels can be visualized, e.g., during therapy of patients suffering from insufficient lymphatic growth, such as in lymphedema, or alternatively during treatment aiming to prevent lymphatic growth, e.g., in tumors, thereby facilitating the monitoring of the therapeutic method of the invention.

Antibodies against LEC-specific TM proteins are also expected to be useful for the isolation of lymphatic endothelial cells.

Antibodies against lymphatic-specific transmembrane proteins, or peptides or small-molecule compounds binding to the extracellular domain of lymphatic-specific TM proteins are expected to be useful in targeting drug delivery to lymphatic endothelial cells, e.g., by coupling an antibody, peptide or small-molecule compound to a cytotoxic or cytostatic compound. Such coupled compounds are useful as therapeutics in the treatment of malignant tumor diseases prone to metastatic spread via the lymphatic system, as well as in ameliorating a symptom associated with any such disease. The antibodies, peptides or small-molecule compounds can also be coupled to stimulatory lymphatic endothelial molecules such as growth factors, cytokines and chemokines to promote stimulation.

Additionally, antibodies against lymphatic-specific TM proteins or peptides, or small-molecule compounds binding to the extracellular domain of lymphatic-specific TM proteins, may be used for targeting of gene therapy, for example, by antibody-coated liposomes (containing proteins, genes or other molecules as cargo) or by viral transducing vectors such as adenoviruses, adeno-associated viruses, lentiviruses, or the like, having modified capsid/envelope proteins. The manipulation of lymphatic endothelial-cell-specific molecules are expected to be applicable to the treatment of disease processes associated with tissue edema due to the relative absence, or relative dysfunction, of lymphatic vessels, which can result from an infection, surgery, radiotherapy or a genetic defect by increasing fluid transport across the lymphatic vessel wall, for example by modulating endothelial cell-cell or cell-matrix interactions or by stimulating transendothelial transport.

The lymphatic endothelial cell molecules are expected to improve the in vitro growth of lymphatic endothelial cells, as well as the in vitro tissue engineering of lymphatic vessels for use in treating disorders or diseases where the lymphatics have been damaged, such as after surgery, in various forms of lymphedema, and in other applications as described herein. Ligands of the cell-surface proteins may further be applied as a coating to various polymeric matrices for the adhesion of cells in, e.g., bioimplants.

Inflammatory, autoimmune and infectious processes involving leukocyte migration and immune recognition, such as migration of antigen-presenting cells into the lymphatic system, including lymph nodes, as well as transendothelial cell trafficking of lymphocytes and other leukocyte subclasses and the homing, survival and function of the various classes of leukocytes can be modulated by targeting endothelial-cell-specific TM proteins, which mediate these cell adhesion processes.

Upregulation of lymphatic-specific genes in, e.g., cancer are expected to be useful as diagnostic markers, and monitoring such upregulated expression with an antibody against a lymphatic endothelial-cell-specific protein, e.g., by immunostaining of tissue(s) or by using a probe hybridizable to a lymphatic endothelial-cell-specific mRNA, e.g., under stringent hybridization conditions as described herein, is contemplated.

Lymphatic endothelial-cell-specific transcription factors are expected to be useful for the differentiation of lymphatic endothelial cells from embryonic stem cells, endothelial precursor cells, or blood vascular endothelial cells.

The lymphatic endothelial transcription factors are expected to improve the in vitro growth of lymphatic endothelial cells, as well as to facilitate in vitro tissue engineering of lymphatic vessels for use in treating disorders or diseases where the lymphatics have been damaged, such as after surgery, in various forms of lymphedemna, and in other applications disclosed herein.

Intracellular signaling proteins participating in signaling pathways regulating lymphatic endothelial cell proliferation, differentiation, apoptosis, migration or adhesion are expected to be useful targets for small-molecule compounds inhibiting these signaling events, and cellular functions dependent on such signaling. Signaling proteins are also expected to participate in VEGFR-3 signaling pathways, and will be useful in modulating cellular activities controlled, at least in part, by VEGFR-3 signaling, such as lymphangiogenesis.

The lymphatic endothelial cell molecules are expected to improve the in vitro growth of lymphatic endothelial cells as well as in vitro tissue engineering of lymphatic vessels for use in treating diseases or disorders where the lymphatics have been damaged, such as after surgery, in various forms of lymphedema, and in other applications as described herein.

Lymphatic-specific transcription factors are also expected to be useful in modulating gene expression in endothelial cells to induce the expression of other lymphatic-specific genes in, for example, blood vascular endothelial cells or endothelial precursor cells.

Lymphatic-specific gene transcripts are expected to provide useful targets for RNA interference (RNAi)-induced inhibition of expression. RNAi technology is expected to be useful in the methods according to the invention, such as therapeutic methods effective in treating hyper- and hypo-proliferative endothelial-cell-associated diseases and disorders, as well as methods of ameliorating a symptom of any such disease or disorder. RNAi methodologies are known in the art and known RNAi technologies are contemplated as useful in various aspects of the invention. See Fire et al., Nature 391:806-811. (1998) and Sharp, P., Genes and Dev. 13:139-141. (1999), each of which is incorporated herein by reference. It is preferred that RNAi compounds be double-stranded RNA molecules corresponding to part or all of a coding region of a desired target for expression.

As noted, several of the new LEC genes encode transcription factors, which may control cellular fate (iroquois-related homeobox gene), and may have an important role in the differentiation of lymphatic endothelial cells. Transcription factors disclosed herein may control transcription of genes involved for example in the proliferation of lymphatic endothelial cells, and may be important molecular regulators of lymphatic growth (Table 5). Lymphatic endothelial cell specific transcription factors can be used for the differentiation of lymphatic endothelial cells from embryonic stem cells, endothelial precursor cells or from blood vascular endothelial cells.

The lymphatic endothelial transcription factors may allow the improved in vitro growth of lymphatic endothelial cells as well as in vitro tissue engineering of lymphatic vessels for use in diseases where the lymphatics have been damaged, such as after surgery and in various forms of lymphedema.

Polynucleotides of the Invention

In general, the isolated polynucleotides of the invention include the LEC and BEC polynucleotides exhibiting differential expression and identified in Tables 3, 4, 14, 15 and 16. The sequences of these polynucleoides are provided in Table 16, associated with their known database accession numbers, where applicable. In Tables 14 and 15, these accession numbers are correlated with unique sequence identifiers, thus permitting identification by sequence identifier of each citation to an accession number. The polynuleotide sequences may include a coding region and may include non-coding flanking sequences, which are readily identifiable by one of skill in the art. The invention contemplates polynucleotides comprising part, or all, of a coding region, with or without flanking regions, e.g., poly A sequences, 5′ non-coding sequences, and the like. The polynucleotides of the present invention also include, but are not limited to, a polynucleotide that hybridizes to the complement of the nucleotide sequence of any one of SEQ ID NOS: 1-30, 45, 47, 49 and 51 under highly stringent hybridization conditions; a polynucleotide that hybridizes to the complement of the nucleotide sequence of any one of SEQ ID NOS: 1-30, 45, 47, 49 and 51 under moderately stringent hybridization conditions; a polynucleotide which is an allelic variant of any polynucleotide recited above; a polynucleotide which encodes a species homologue of any of the proteins recited above; or a polynucleotide that encodes a polypeptide comprising a specific domain or truncation of the polypeptide of any one of SEQ ID NOS: 31-44, 46, 48, 50 and 52. Such polynucleotides hybridize under the above conditions to the complement of any one of SEQ ID NOS: 1-30, 45, 47,49 and 51 or to a fragment of any one of SEQ ID NOS: 1-30, 45, 47, 49 and 51 wherein the fragment is greater than at least about 10 bp, and, in alternate embodiments, is about 20 to about 50 bp, or is greater than about 100 bp, 200 bp, 300 bp, 400 bp, 500 bp, 600 bp, 700 bp, or 800 bp, where appropriate.

The polynucleotides of the invention also provide polynucleotides that are variants of the polynucleotides recited above. Typically, such a variant sequence varies from one of those listed herein by no more than about 20%, ie., the number of individual nucleotide substitutions, additions, and/or deletions in a similar sequence, as compared to the corresponding reference sequence, divided by the total number of nucleotides in the variant sequence is about 0.2 or less. Such a sequence is said to have 80% sequence identity to the listed sequence. Such a variant sequence can be routinely identified by applying the foregoing algorithm.

In one embodiment, a variant polynucleotide sequence of the invention varies from a listed sequence by no more than 10%, i.e., the number of individual nucleotide substitutions, additions, and/or deletions in a variant sequence, as compared to the corresponding reference sequence, divided by the total number of nucleotides in the variant sequence is about 0.1 or less. Such a sequence is said to have 90% sequence identity to the listed sequence. Such a variant sequence can be routinely identified by applying the foregoing algorithm.

In an alternate embodiment a variant sequence of the invention varies from a listed sequence by no more than by no more than 5%, i.e., the number of individual nucleotide substitutions, additions, and/or deletions in a variant sequence, as compared to the corresponding reference sequence, divided by the total number of nucleotides in the variant sequence is about 0.05 or less. Such a sequence is said to have 95% sequence identity to the listed sequence. Such a variant sequence can be routinely identified by applying the foregoing algorithm.

In yet another alternate embodiment, a variant sequence of the invention varies from a listed sequence by no more than 2%, ie., the number of individual nucleotide substitutions, additions, and/or deletions in a variant sequence, as compared to the corresponding reference sequence, divided by the total number of nucleotides in the variant sequence is about 0.02 or less. Such a sequence is said to have 98% sequence identity to the listed sequence. Such a variant sequence can be routinely identified.

A polynucleotide according to the invention can be joined to any of a variety of other nucleotide sequences by well-established recombinant DNA techniques (see Sambrook J et al. (2d Ed.; 1989) Molecular Cloning: A Laboratory Manual, Cold Spring Harbor Laboratory, Cold Spring Harbor, N.Y.). Useful nucleotide sequences for joining to polypeptides include an assortment of vectors, e.g., plasmids, cosmids, lambda phage derivatives, phagemids, and the like, that are well known in the art. Accordingly, the invention also provides a vector including a polynucleotide of the invention and a host cell containing the polynucleotide. In general, the vector contains an origin of replication functional in at least one organism, convenient restriction endonuclease sites, and a selectable marker for the host cell. Vectors according to the invention include expression vectors, replication vectors, probe generation vectors, sequencing vectors, and retroviral vectors. A host cell according to the invention can be a prokaryotic or eukaryotic cell and can be a unicellular organism or part of a multicellular organism. Large numbers of suitable vectors and promoters are known to those of skill in the art and are commercially available for generating the recombinant constructs of the present invention.

The sequences falling within the scope of the present invention are not limited to the specific sequences herein described, but also include allelic variations thereof. Allelic variations can be routinely determined by comparing the sequence provided in any one of SEQ ID NOS: 1-30, 45, 47, 49 and 51, a representative intermediate fragment thereof, or a nucleotide sequence at least 99.9% identical to any one of SEQ ID NOS: 1-30, 45, 47, 49 and 51 with a sequence from another isolate of the same species. Furthermore, to accommodate codon variability, the invention includes nucleic acid molecules coding for the same amino acid sequences as do the specific open reading frames (ORFs) disclosed herein. In other words, in the coding region of an ORF, substitution of one codon for another which encodes the same amino acid is expressly contemplated.

Unless provided for otherwise here, all terms are defined as is known in the art, for example as employed in U.S. Pat. No. 6,350,447, incorporated herein by reference.

Also contemplated are antisense polynucleotides based on the sequence of any of the LEC or BEC polynucleotides according to the invention. Such antisense polynucleotides are substantially complementary (e.g., at least 90% complementarity), and preferably perfectly complementary, to sequences of the polynucleotides of the invention, or fragments thereof, set out in the sequence listing, Tables 3, 4, 14-16, and throughout this disclosure that are differentially expressed in LECs and BECs. These polynucleotide sequences include any of SEQ ID NOS: 1-30, 45, 47, 49 and 51, or a fragment thereof comprising at least 10 contiguous nucleotides. Antisense nucleic acid comprises a nucleotide sequence that is complementary to a “sense” nucleic acid encoding a protein (e.g., complementary to the coding strand of a double-stranded cDNA molecule or complementary to an mRNA sequence). Methods for designing and optimizing antisense nucleotides are described in Lima et al., (J Biol Chem,; 272:626-38. 1997) and Kurreck et al., (Nucleic Acids Res.,; 30:1911-8. 2002). In one aspect, antisense nucleic acid molecules are provided that comprise a sequence complementary to at least about 10, 25, 50, 100, 250 or 500 nucleotides or an entire coding strand. An antisense nucleic acid of the invention can be constructed using chemical synthesis or enzymatic ligation reactions using procedures known in the art.

In one embodiment, an antisense nucleic acid molecule is antisense to a “coding region” of the coding strand of a nucleotide sequence encoding a polypeptide of the invention. The term “coding region” refers to the region of the nucleotide sequence comprising codons which are translated into amino acid residues. In another embodiment, the antisense nucleic acid molecule is antisense to a “conceding region” of the coding strand of a nucleotide sequence encoding the polynucleotide. The term “conceding region” refers to 5′ and 3′ sequences which flank the coding region that are not translated into amino acids (i.e., also referred to as 5′ and 3′ untranslated regions).

Antisense nucleic acids of the invention can be designed according to the rules of Watson and Crick or Hoogsteen base pairing. The antisense nucleic acid molecule can be complementary to the entire coding region of the mRNA of the polynucleotide of the invention, but more preferably is an oligonucleotide that is antisense to only a portion of the coding or noncoding region of the mRNA. An antisense oligonucleotide can be, for example, about 5, 10, 15, 20, 25, 30, 35, 40, 45, or 50 nucleotides in length. An antisense nucleic acid of the invention can be constructed using chemical synthesis or enzymatic ligation reactions using procedures known in the art. For example, an antisense nucleic acid (e.g., an antisense oligonucleotide) can be chemically synthesized using naturally occurring nucleotides or variously modified nucleotides designed to increase the biological stability of the molecules or to increase the physical stability of the duplex formed between the antisense and sense nucleic acids (e.g., phosphorothioate derivatives and acridine substituted nucleotides can be used).

The antisense nucleic acid molecules of the invention are typically administered to a subject or generated in situ such that they hybridize or bind to cellular mRNA and/or genomic DNA encoding the complementary polynucleotide, thereby inhibiting expression of the protein (e.g., by inhibiting transcription and/or translation). The hybridization can reflect conventional nucleotide complementarity to form a stable duplex, or, for example, in the case of an antisense nucleic acid molecule that binds to DNA duplexes, through specific interactions in the major groove of the double helix.

An example of a route of administration of antisense nucleic acid molecules of the invention includes direct injection at a tissue site. Alternatively, antisense nucleic acid molecules can be modified to target selected cells and then administered systemically. For example, for systemic administration, antisense molecules can be modified such that they specifically bind to receptors or antigens expressed on a selected cell surface (e.g., by linking the antisense nucleic acid molecules to peptides or antibodies that bind to cell surface receptors or antigens). Additional routes of antisense therapy may be used in the invention, e.g., topical administration, transdermal administration [reviewed by Brand in Curr Opin. Mol. Ther. 3.244-8. 2001] antisense administration using nanoparticulate systems [Lambert et al., Adv. Drug. Deliv. Rev. 47:99-112. 2001], or administration of antisense nucleotides conjugated with peptide [Juliano et al., Curr. Opin. Mol. Ther. 2:297-303. 2000].

The invention further contemplates use of the polynucleotides of the invention for gene therapy or in recombinant expression vectors which produce polynucleotides or polypeptides of the invention that can regulate an activity of LEC genes, and are useful in therapy of LEC disorders such as lymphedema. Delivery of a functional gene encoding a polypeptide of the invention to appropriate cells is effected ex vivo, in situ, or in vivo by use of vectors, including viral vectors (e.g., adenovirus, adeno-associated virus, or a retrovirus), or ex vivo by use of physical DNA transfer methods (e.g., liposomes or chemical treatments). See, for example,. Anderson, Nature, supplement to vol. 392, no. 6679, pp. 25-20 (1998). For additional reviews of gene therapy technology see Friedmann, (Science, 244: 1275-1281. 1989); Verma, (Scientific American: 263:68-72, 81-84. 1990); and Miller, (Nature, 357: 455-460. 1992). Introduction of any one of the nucleotides of the present invention or a gene encoding a polypeptide of the invention can also be accomplished with extrachromosomal substrates (transient expression) or artificial chromosomes (stable expression). Cells may also be cultured ex vivo in the presence of proteins of the present invention in order to proliferate or to produce a desired effect on, or activity in, such cells. In another embodiment, cells comprising vectors expressing the polynucleotides or polypeptides of the invention may be cultured ex vivo and administered to an individual in need of treatment for an LEC disease or disorder.

Given the foregoing disclosure of the nucleic acid constructs, it is possible to produce the gene product of any of the genes comprising the sequence of any of SEQ ID NOS: 1-30, 45, 47, 49 and 51 by routine recombinant DNA/RNA techniques. A variety of expression vector/host systems may be utilized to contain and express the coding sequence. These include, but are not limited to, microorganisms such as bacteria transformed with recombinant bacteriophage, plasmid, phagemid, or cosmid DNA expression vectors; yeast transformed with yeast expression vectors; insect cell systems infected with viral expression vectors (e.g., baculovirus); plant cell systems transfected with virus expression vectors (e.g., Cauliflower Mosaic Virus, CaMV; Tobacco Mosaic Virus, TMV) or transformed with bacterial expression vectors (e.g., Ti or pBR322 plasmid); or even animal cell systems. Mammalian cells that are useful in recombinant protein productions include, but are not limited to, VERO cells, HeLa cells, Chinese hamster ovary (CHO) cells, COS cells (such as COS-7), WI38, BHK, HepG2, 3T3, RIN, MDCK, A549, PC12, K562 and HEK 293 cells.

Polypeptides of the Invention

In general, the isolated LEC and BEC polypeptides of the invention are encoded by the above-described differentially expressed LEC and BEC polynuleotides of the invention. The sequences of the LEC and BEC polypeptides are provided in Table 16, associated with their known database accession numbers, where applicable. In Tables 14 and 15, these accession numbers are correlated with unique sequence identifiers, thus permitting identification by sequence idenfier of 4each citation to an accession number. The isolated polypeptides of the invention include, but are not limited to, a polypeptide comprising: the amino acid sequences set forth as any one of SEQ ID NOS.: 31-44, 46, 48, 50 and 52 or an amino acid sequence encoded by any one of the nucleotide sequences set forth in SEQ ID NOS.: 1-30, 45, 47, 49 and 51, or the corresponding full length or mature protein. The invention also provides biologically active or immunologically active variants of any of the amino acid sequences set forth as SEQ ID NOS.: 31-44, 46, 48, 50 and 52, or the corresponding full length or mature protein suitable variant polypeptides have sequences that are at least about 65%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, 86%, 87%, 88%, 89%, at least about 90%, 91%, 92%, 93%, 94%, typically at least about 95%, 96%, 97%, more typically at least about 98%, or most typically at least about 99% amino acid identity, that retain biological activity. Fragments of the proteins of the present invention which comprise at least 10 contiguous amino acids of a sequence disclosed herein and that are capable of exhibiting a biological activity of the corresponding full length protein are also encompassed by the present invention.

The protein coding sequence is identified in the sequence listing by translation of the disclosed nucleotide sequences. The mature form of such protein may be obtained by expression of a full-length polynucleotide in a suitable mammalian cell or other host cell. The sequence of the mature form of the protein is also determinable from the amino acid sequence of the full-length form. Where proteins of the present invention are membrane bound, soluble forms of the proteins are also provided. In such forms, part or all of the regions causing the proteins to be membrane bound are deleted so that the proteins are capable of being fully secreted from the cell in which it is expressed.

A variety of methodologies known in the art can be utilized to obtain any one of the isolated polypeptides or proteins of the present invention. At the simplest level, the amino acid sequence can be synthesized using commercially available peptide synthesizers. The polypeptides and proteins of the present invention can alternatively be purified from cells which have been altered to express the desired polypeptide or protein. As used herein, a cell is said to be altered to express a desired polypeptide or protein when the cell, through genetic manipulation, is made to produce a polypeptide or protein which it normally does not produce or which the cell normally produces at a lower level. One skilled in the art can readily adapt procedures for introducing and expressing either recombinant or synthetic sequences into eukaryotic or prokaryotic cells in order to generate a cell which produces one of the polypeptides or proteins of the present invention.

A “fragment” of a polypeptide is meant to refer to any portion of the molecule, such as the peptide core, a variant of the peptide core, or an extracellular region of the polypeptide. A “variant” of a polypeptide is meant to refer to a molecule substantially similar in structure and biological activity to either the entire molecule, or to a fragment thereof Thus, provided that two molecules possess a similar activity, they are considered variants as that term is used herein even if the composition or secondary, tertiary, or quaternary structure of one of the molecules is not identical to that found in the other, or if the sequence of amino acid residues is not identical. An “analogue” of a polypeptide or genetic sequence is meant to refer to a protein or genetic sequence substantially similar in function and structure to the isolated polypeptide or genetic sequence.

It is understood herein that conservative amino acid substitutions can be performed to a purified and isolated polypeptide comprising any one of the sequences of SEQ ID NOS.: 31-44, 46, 48, 50 and 52 which are likely to result in a polypeptide that retains biological or immunological activity, especially if the number of such substitutions is small. By “conservative amino acid substitution” is meant substitution of an amino acid with an amino acid having a side chain of a similar chemical character. Similar amino acids for making conservative substitutions include those having an acidic side chain (glutamic acid, aspartic acid); a basic side chain (arginine, lysine, histidine); a polar amide side chain (glutamine, asparagine); a hydrophobic, aliphatic side chain (leucine, isoleucine, valine, alanine, glycine); an aromatic side chain (phenylalanine, tryptophan, tyrosine); a small side chain (glycine, alanine, serine, threonine, methionine); or an aliphatic hydroxyl side chain (serine, threonine).

Microarrays

Another aspect of the invention is a composition comprising a plurality of polynucleotide probes for use in detecting gene expression pattern(s) characteristic of particular cell type(s) and for detecting changes in the expression pattern of a particular cell type, e.g., lymphatic endothelial cells. For example, the invention comprehends an array, such as a microarray, comprising polynucleotides having at least 10 contiguous nucleotides selected from the polynucleotide sequences presented in the sequence listing.

Also contemplated are microarrays comprising polynucleotides having at least 10 contiguous nucleotides selected from the group of SEQ ID NOS: 1-30, 45, 47, 49 and 51. Microarrays of the invention comprise at least 3 polynucleotides, wherein each enumerated polynucleotide has a distinct sequence selected from the group consisting of SEQ ID NOS:1-30, 45, 47, 49 and 51. Such microarrays may also have duplicate polynucleotides and additional polynucleotides, e.g., control polynucleotides for use in hybridization-based assays using the microarray. Arrays, including microarrays, having more than three distinct polynucleotides according to the invention, such as at least five, seven, nine, 20, 50 or more such polynucleotides, will be recognized as arrays according to the invention having the capability of yielding subtle distinctions between biological samples such as various endothelial cell types, or of providing a different, and typically greater, level of confidence in the various uses of such arrays, e.g., in screening for particular endothelial cells, in screening for abnormal or diseases cells and tissues, and the like.

The term “microarray” refers to an ordered arrangement of hybridizable array elements. The array elements are arranged so that there are preferably at least three or more different array elements, more preferably at least 100 array elements, and most preferably at least 1,000 array elements, on a solid support. Preferably, the solid support is a 1 cm² substrate surface, bead, paper, nylon or other type of membrane, filter, chip, glass slide, or any other suitable solid support. The hybridization signal from each of the array elements is individually distinguishable. In a preferred embodiment, the array elements comprise polynucleotide probes.

Hybridization means contacting two or more nucleic acids under conditions suitable for base pairing. Hybridization includes interaction between partially or perfectly complementary nucleic acids. Suitable hybridization conditions are well known to those of skill in the art. In certain applications, it is appreciated that lower stringency conditions may be required. Under these conditions, hybridization may occur even though the sequences of the interacting strands are not perfectly complementary, being mismatched at one or more positions. Conditions may be rendered less stringent by adjusting conditions in accordance with the knowledge in the art, e.g., increasing salt concentration and/or decreasing temperature. Suitable hybridization conditions are those conditions that allow the detection of gene expression from identifiable expression units such as genes. Preferred hybridization conditions are stringent hybridization conditions, such as hybridization at 42° C. in a solution (ie., a hybridization solution) comprising 50% formamide, 1% SDS, 1 M NaCl, 10% dextran sulfate, and washing for 30 minutes at 65° C. in a wash solution comprising 1×SSC and 0.1% SDS. It is understood in the art that conditions of equivalent stringency can be achieved through variation of temperature and buffer, or salt concentration, as described in Ausubel, et al. (Eds.), Protocols in Molecular Biology, John Wiley & Sons (1994), pp. 6.0.3 to 6.4.10. Modifications in hybridization conditions can be empirically determined or precisely calculated based on the length and the percentage of guanosine/cytosine (GC) base pairing of the probe. The hybridization conditions can be calculated as described in Sambrook, et al., (Eds.), Molecular Cloning: A Laboratory Manual, Cold Spring Harbor Laboratory Press: Cold Spring Harbor, N.Y. (2d. Ed.; 1989), pp. 9.47 to 9.51.

One method of using probes and primers of the invention is in the detection of gene expression in human cells. Normally, the target will be expressed RNAs, although genomic DNA or a cDNA library may be screened. By varying the stringency of hybridization and the target binding site (i.e., the sequence of the probe, corresponding to a subset of one of the sequences set forth at SEQ ID NOS: 1-30, 45, 47, 49 and 51), different degrees of homology are expected to result in hybridization.

The microarray can be used for large-scale genetic or gene expression analysis of a large number of target polynucleotides. The microarray can also be used in the diagnosis of diseases and in the monitoring of treatments. Further, the microarray can be employed to investigate an individual's predisposition to a disease. Furthermore, the microarray can be employed to investigate cellular responses to infection, drug treatment, and the like.

The nucleic acid probes can be genomic DNA or cDNA or mRNA polynucleotides or oligonucleotides, or any RNA-like or DNA-like material, such as peptide nucleic acids, branched DNAs, and the like. The probes can be sense or antisense nucleotide probes. Where target polynucleotides are double-stranded, the probes may be either sense or antisense strands. Where the target polynucleotides are single-stranded, the probes are complementary single strands. In one embodiment, the probes are cDNAs. The size of the DNA sequence of interest may vary and is preferably from 100 to 10,000 nucleotides, more preferably from 150 to 3,500 nucleotides.

The probes can be prepared using a variety of synthetic or enzymatic techniques, which are well known in the art. The probes can be synthesized, in whole or in part, using chemical methods well known in the art (Caruthers et al., Nucleic Acids Res., Symp. Ser., 215-233, 1980).

Pharmaceutical Formulations and Routes of Administration

A protein of the present invention (from whatever source derived, such as from recombinant and non-recombinant sources) may be administered to a patient in need, by itself, or in pharmaceutical compositions where it is mixed with suitable carriers, diluents, adjuvants or excipients at doses to treat or ameliorate a variety of disorders. Such a composition may also contain (in addition to protein and a carrier) diluents, fillers, salts, buffers, stabilizers, solubilizers, and other materials well known in the art. The term “pharmaceutically acceptable” means a non-toxic material that does not interfere with the effectiveness of the biological activity of the active ingredient(s). The characteristics of the carrier will depend on the route of administration. The pharmaceutical composition of the invention may also contain cytokines, chemokines, lymphokines, growth factors, or other hematopoietic factors such as a PDGF, a VEGF (particularly a VEGF-C or a VEGF-D), VEGFR-3 (including soluble VEGFR-3 peptides comprising an extracellular domain), M-CSF, GM-CSF, TNF, IL-1, IL-2, IL-3, IL-4, IL-5, IL-6, IL-7, IL-8, IL-9, IL-10, IL-11, IL-12, IL-13, IL-14, IL-15, IFN, TNF0, TNF1, TNF2, G-CSF, Meg-CSF, thrombopoietin, stem cell factor, and erythropoietin. Various forms of these polypeptides are contemplated as well, such as isolated holoproteins, subunits, fragments (e.g., soluble fragments), and peptide fusions. The pharmaceutical composition may further contain other agents which either enhance the activity of the protein or complement its activity or use in treatment. Such additional factors and/or agents may be included in the pharmaceutical composition to produce a synergistic effect with a protein of the invention, or to minimize side effects. Conversely, a protein of the present invention may be included in formulations of the particular cytokine, lymphokine, other hematopoietic factor, thrombolytic or anti-thrombotic factor, or anti-inflammatory agent to minimize side effects of the cytokine, lymphokine, other hematopoietic factor, thrombolytic or anti-thrombotic factor, or anti-inflammatory agent. A protein of the present invention may be active in multimers (e.g., heterodimers or homodimers) or complexes with itself or other proteins. As a result, pharmaceutical compositions of the invention may comprise a protein of the invention in such muiltimeric or complexed form.

Techniques for formulation and administration of the compounds of the instant application may be found in “Remington's Pharmaceutical Sciences,” Mack Publishing Co., Easton, Pa., latest edition. A therapeutically effective dose further refers to that amount of the compound sufficient to result in amelioration of symptoms, e.g., treatment, healing, prevention or amelioration of the relevant medical condition, or an increase in rate of beneficial change, healing, prevention or amelioration of such conditions. When applied to an individual active ingredient, administered alone, a therapeutically effective dose refers to that ingredient alone. When applied to a combination, a therapeutically effective dose refers to combined amounts of the active ingredients that result in the therapeutic effect, whether administered in combination, serially or simultaneously.

In practicing methods of treatment or use of the present invention, a therapeutically effective amount of protein of the present invention is administered to a mammal having a condition or disorder to be treated. Protein of the present invention may be administered in accordance with the method of the invention either alone or in combination with other therapies such as treatments employing cytokines, lymphokines or other hematopoietic factors. When co-administered with one or more cytokines, lymphokines or other hematopoietic factors, a protein of the invention may be administered either simultaneously with the cytokine(s), lymphokine(s), other hematopoietic factor(s), thrombolytic or anti-thrombotic factors, or sequentially. If administered sequentially, the attending physician will decide on the appropriate sequence of administering a protein of the invention in combination with a cytokine(s), lymphokine(s), other hematopoietic factor(s), thrombolytic or anti-thrombotic factors.

Routes of Administration

Suitable routes of administration may, for example, include oral, rectal, transmucosal, or intestinal administration; parenteral delivery, including intramuscular, subcutaneous, intramedullary injections, as well as intrathecal, direct intraventricular, intravenous, intraperitoneal, intranasal, or intraocular injections. Administration of protein of the present invention used in the pharmaceutical composition or to practice the method of the present invention is carried out in a variety of conventional ways, such as oral ingestion, inhalation, topical application or cutaneous, subcutaneous, intraperitoneal, parenteral or intravenous injection. Intravenous administration to a mammal, such as a human patient, is preferred. Alternately, one may administer the compound in a local rather than systemic manner, for example, via injection of the compound at the site of intended action.

Compositions/Formulations

Pharmaceutical compositions for use in accordance with the present invention thus may be formulated in a conventional manner using one or more physiologically acceptable carriers comprising excipients and auxiliaries which facilitate processing of the active compounds into preparations which can be used pharmaceutically. These pharmaceutical compositions may be manufactured in a manner that is itself known, e.g., by means of conventional mixing, dissolving, granulating, dragee-making, levigating, emulsifying, encapsulating, entrapping or lyophilizing processes. Proper formulation is dependent upon the route of administration chosen. When a therapeutically effective amount of protein of the present invention is administered orally, protein of the present invention will be in the form of a tablet, capsule, powder, solution or elixir. When administered in tablet form, the pharmaceutical composition of the invention may additionally contain a solid carrier such as a gelatin or an adjuvant. The tablet, capsule, and powder contain from about 5 to 95% protein of the present invention, and preferably firom about 25 to 90% protein of the present invention. When administered in liquid form, a liquid carrier such as water, petroleum, oils of animal or plant origin such as peanut oil, mineral oil, soybean oil, or sesame oil, or synthetic oils may be added. The liquid form of the pharmaceutical composition may further contain physiological saline solution, dextrose or other saccharide solution, or glycols such as ethylene glycol, propylene glycol or polyethylene glycol. When administered in liquid form, the pharmaceutical composition contains from about 0.5 to 90% by weight of protein of the present invention, and preferably from about 1 to 50% protein of the present invention.

When a therapeutically effective amount of protein of the present invention is administered by intravenous, cutaneous or subcutaneous injection, protein of the present invention will be in the form of a pyrogen-free, parenterally acceptable aqueous solution. The preparation of such parenterally acceptable protein solutions, having due regard to pH, isotonicity, stability, and the like, is within the skill in the art. A preferred pharmaceutical composition for intravenous, cutaneous, or subcutaneous injection should contain, in addition to protein of the present invention, an isotonic vehicle such as Sodium Chloride Injection, Ringer's Injection, Dextrose Injection, Dextrose and Sodium Chloride Injection, Lactated Ringer's Injection, or other vehicle as known in the art. The pharmaceutical composition of the present invention may also contain stabilizers, preservatives, buffers, antioxidants, or other additives known to those of skill in the art. For injection, the agents of the invention may be formulated in aqueous solutions, preferably in physiologically compatible buffers such as Hanks' solution, Ringer's solution, or physiological saline buffer. For transmucosal administration, penetrants appropriate to the barrier to be permeated are used in the formulation. Such penetrants are generally known in the art.

For oral administration, the compounds can be formulated readily by combining the active compounds with pharmaceutically acceptable carriers well known in the art. Such carriers enable the compounds of the invention to be formulated as tablets, pills, dragees, capsules, liquids, gels, syrups, slurries, suspensions and the like, for oral ingestion by a patient to be treated. Pharmaceutical preparations for oral use can be obtained by combination with a solid excipient, optionally grinding a resulting mixture, and processing the mixture of granules, after adding suitable auxiliaries, if desired, to obtain tablets or dragee cores. Suitable excipients are, in particular, fillers such as sugars, including lactose, sucrose, mannitol, or sorbitol; cellulose preparations such as, for example, maize starch, wheat starch, rice starch, potato starch, gelatin, gum tragacanth, methyl cellulose, hydroxypropylmethyl-cellulose, sodium carboxymethylcellulose, and/or polyvinylpyrrolidone (PVP). If desired, disintegrating agents may be added, such as the cross-linked polyvinyl pyrrolidone, agar, or alginic acid or a salt thereof such as sodium alginate. Dragee cores are provided with suitable coatings. For this purpose, concentrated sugar solutions may be used, which may optionally contain gum arabic, talc, polyvinyl pyrrolidone, carbopol gel, polyethylene glycol, and/or titanium dioxide, lacquer solutions, and suitable organic solvents or solvent mixtures. Dyestuffs or pigments may be added to the tablets or dragee coatings for identification or to characterize different combinations of active compound doses.

Pharmaceutical preparations which can be used orally include push-fit capsules made of gelatin, as well as soft, sealed capsules made of gelatin and a plasticizer, such as glycerol or sorbitol. The push-fit capsules can contain the active ingredients in admixture with filler such as lactose, binders such as starches, and/or lubricants such as talc or magnesium stearate and, optionally, stabilizers. In soft capsules, the active compounds may be dissolved or suspended in suitable liquids, such as fatty oils, liquid paraffin, or liquid polyethylene glycols. In addition, stabilizers may be added. All formulations for oral administration should be in dosages suitable for such administration. For buccal administration, the compositions may take the form of tablets or lozenges formulated in conventional manner.

For administration by inhalation, the compounds for use according to the present invention are conveniently delivered in the form of an aerosol spray presentation from pressurized packs or a nebuliser, with the use of a suitable propellant, e.g., dichlorodifluoromethane, trichlorofluoromethane, dichlorotetrafluoroethane, carbon dioxide or other suitable gas. In the case of a pressurized aerosol the dosage unit may be determined by providing a valve to deliver a metered amount. Capsules and cartridges of, e.g., gelatin for use in an inhaler or insufflator may be formulated containing a powder mix of the compound and a suitable powder base such as lactose or starch. The compounds may be formulated for parenteral administration by injection, e.g., by bolus injection or continuous infusion. Formulations for injection may be presented in unit dosage form, e.g., in ampoules or in multi-dose containers, with an added preservative. The compositions may take such forms as suspensions, solutions or emulsions in oily or aqueous vehicles, and may contain formulatory-agents such as suspending, stabilizing and/or dispersing agents.

Pharmaceutical formulations for parenteral administration include aqueous solutions of the active compounds in water-soluble form. Additionally, suspensions of the active compounds may be prepared as appropriate oily injection suspensions. Suitable lipophilic solvents or vehicles include fatty oils such as sesame oil, or synthetic fatty acid esters, such as ethyl oleate or triglycerides, or liposomes. Aqueous injection suspensions may contain substances which increase the viscosity of the suspension, such as sodium carboxymethyl cellulose, sorbitol, or dextran. Optionally, the suspension may also contain suitable stabilizers or agents which increase the solubility of the compounds to allow for the preparation of highly concentrated solutions. Alternatively, the active ingredient may be in powder form for constitution with a suitable vehicle, e.g., sterile pyrogen-free water, before use.

The compounds may also be formulated in rectal compositions such as suppositories or retention enemas, e.g., containing conventional suppository bases such as cocoa butter or other glycerides. In addition to the formulations described previously, the compounds may also be formulated as a depot preparation. Such long-acting formulations may be administered by implantation (for example subcutaneously or intramuscularly) or by intramuscular injection. Thus, for example, the compounds may be formulated with suitable polymeric or hydrophobic materials (for example as an emulsion in an acceptable oil) or ion exchange resins, or as sparingly soluble derivatives, for example, as a sparingly soluble salt.

A pharmaceutical carrier for the hydrophobic compounds of the invention is a cosolvent system comprising benzyl alcohol, a nonpolar surfactant, a water-miscible organic polymer, and an aqueous phase. The cosolvent system may be the VPD co-solvent system. VPD is a solution of 3% w/v benzyl alcohol, 8% w/v of the nonpolar surfactant polysorbate 80, and 65% w/v polyethylene glycol 300, made up to volume in absolute ethanol. The VPD co-solvent system (VPD:5W) consists of VPD diluted 1:1 with a 5% dextrose-in-water solution. This co-solvent system dissolves hydrophobic compounds well, and itself produces low toxicity upon systemic administration. Naturally, the proportions of a co-solvent system may be varied considerably without destroying its solubility and toxicity characteristics. Furthermore, the identity of the co-solvent components may be varied: for example, other low-toxicity nonpolar surfactants may be used instead of polysorbate 80; the fraction size of polyethylene glycol may be varied; other biocompatible polymers may replace polyethylene glycol, e.g., polyvinyl pyrrolidone; and other sugars or polysaccharides may substitute for dextrose. Alternatively, other delivery systems for hydrophobic pharmaceutical compounds may be employed. Liposomes and emulsions are well known examples of delivery vehicles or carriers for hydrophobic drugs. Certain organic solvents such as dimethylsulfoxide also may be employed, although usually at the cost of greater toxicity. Additionally, the compounds may be delivered using a sustained-release system, such as semipermeable matrices of solid hydrophobic polymers containing the therapeutic agent. Various sustained-release materials have been established and are well known by those skilled in the art. Sustained-release capsules may, depending on their chemical nature, release the compound over a time period of a few weeks up to over 100 days. Depending on the chemical nature and the biological stability of the therapeutic reagent, additional strategies for protein stabilization may be employed.

The pharmaceutical compositions also may comprise suitable solid or gel-phase carriers or excipients. Examples of such carriers or excipients include but are not limited to calcium carbonate, calcium phosphate, various sugars, starches, cellulose derivatives, gelatin, and polymers such as polyethylene glycols. Many of the proteinase-inhibiting compounds of the invention may be provided as salts with pharmaceutically compatible counterions. Such pharmaceutically acceptable base addition salts are those salts which retain the biological effectiveness and properties of the free acids and which are obtained by reaction with inorganic or organic bases such as sodium hydroxide, magnesium hydroxide, ammonia, trialkylamine, dialkylamine, monoalkylamine, dibasic amino acids, sodium acetate, potassium benzoate, triethanol amine, and the like.

The pharmaceutical compositions of the invention may be in the form of a complex of a protein(s) of the present invention along with protein or peptide antigens. The pharmaceutical compositions of the invention may be in the form of a liposome in which protein of the present invention is combined, in addition to other pharmaceutically acceptable carriers, with amphipathic agents such as lipids which exist in aggregated form as micelles, insoluble monolayers, liquid crystals, or lamellar layers in aqueous solution. Suitable lipids for liposomal formulation include, without limitation, monoglycerides, diglycerides, sulfatides, lysolecithin, phospholipids, saponin, bile acids, and the like. Preparation of such liposomal formulations is within the level of skill in the art, as disclosed, for example, in U.S. Pat. Nos. 4,235,871; 4,501,728; 4,837,028; and 4,737,323, each of which is incorporated herein by reference.

The amount of protein of the invention in the pharmaceutical composition will depend upon the nature and severity of the condition being treated, and on the nature of prior treatments which the patient has undergone. Ultimately, the attending physician will decide the amount of protein of the present invention with which to treat each individual patient. Initially, the attending physician will administer low doses of protein of the present invention and observe the patient's response. Larger doses of protein of the present invention may be administered until the optimal therapeutic effect is obtained for the patient, and at that point the dosage is not increased further. It is contemplated that the various pharmaceutical compositions used to practice the methods of the invention should contain about 0.01 μg to about 100 mg (preferably about 0.1 μg to about 10 mg, more preferably about 0.1 μg to about 1 mg) of protein of the invention per kg body weight. When administered, the therapeutic composition for use in this invention is in a pyrogen-free, physiologically acceptable form. Therapeutically useful agents other than a protein of the invention which may also optionally be included in the composition as described above, may alternatively or additionally, be administered simultaneously or sequentially with the composition in the methods of the invention.

Polynucleotides of the present invention can also be used for gene therapy. Such polynucleotides can be introduced either in vivo or ex vivo into cells for expression in a mammalian subject. Polynucleotides of the invention may also be administered by other known methods for introduction of nucleic acid into a cell or organism (including, without limitation, in the form of viral vectors or naked DNA). Cells may also be cultured ex vivo in the presence of proteins of the present invention in order to proliferate or to produce a desired effect on or activity in such cells. Treated cells can then be introduced in vivo for therapeutic purposes.

Effective Dosage

Pharmaceutical compositions suitable for use in the present invention include compositions wherein the active ingredients are contained in an effective amount to achieve an intended purpose. More specifically, a therapeutically effective amount means an amount effective to prevent development of, or to alleviate the existing symptoms of, the subject being treated. Suitable properties that may be used in determining effective dosages include measurements of LEC and/or BEC growth stimulation or inhibition, rates or extent of cell differentiation into LECs and/or BECs, tendencies of cell expression patterns to shift towards or away from LEC- or BEC-specific expression patterns, and the like. Determination of the effective amounts is well within the capability of those skilled in the art, especially in light of the detailed disclosure provided herein. For any compound used in a method of the invention, the therapeutically effective dose can be estimated initially from cell culture assays. For example, for inhibitory methods, a dose can be formulated in animal models to achieve a circulating concentration range that includes the IC₅₀ as determined in cell culture (i.e., the concentration of the test compound which achieves a half-maximal inhibitory concentration). Such information can be used to more accurately determine useful doses in humans.

A therapeutically effective dose refers to that amount of the compound that results in amelioration of symptoms or, in the case of life-threatening conditions, a prolongation of survival in a patient. Toxicity and therapeutic efficacy of such compounds can be determined by standard pharmaceutical procedures in cell cultures or experimental animals, e.g., for determining the LD₅₀ (the dose lethal to 50% of the population) and the ED₅₀ (the dose therapeutically effective in 50% of the population). The dose ratio between toxic and therapeutic effects is the therapeutic index and it can be expressed as the ratio between LD₅₀ and ED₅₀. Compounds which exhibit high therapeutic indices are preferred. The data obtained from these cell culture assays and animal studies can be used in formulating a range of dosage for use in human. The dosage of such compounds lies preferably within a range of circulating concentrations that include the ED₅₀ with little or no toxicity. The dosage may vary within this range depending upon the dosage form employed and the route of administration utilized. The exact formulation, route of administration and dosage can be chosen by the individual physician in view of the patient's condition. See, e.g., Fingl et al., 1975, in “The Pharmacological Basis of Therapeutics”, Ch. 1 p. 1.

The amount of composition administered will, of course, be dependent on the subject being treated, on the subject's weight, the severity of the affliction, the manner of administration and the judgment of the prescribing physician.

Packaging

The compositions may, if desired, be presented in a pack or dispenser device which may contain one or more unit dosage forms containing the active ingredient. The pack may, for example, comprise metal or plastic foil, such as a blister pack. The pack or dispenser device may be accompanied by instructions for administration. Compositions comprising a compound of the invention formulated in a compatible pharmaceutical carrier may also be prepared, placed in an appropriate container, and labelled for treatment of an indicated condition.

In addition, the invention comprehends a use of such a composition to manufacture a medicament for the treatment of a cell or an organism, such as a human patient, having a hyperproliferative or hypoproliferative disorder of a LEC and/or BEC, such as lymphedema, lymphangioma, lymphangiomyeloma, lymphangiomatosis, lymphangiectasis, Iymphosarcoma, or lymphangiosclerosis, comprising administering an effective amount, or dose, of a composition according to the invention to the cell or organism. Suitable compositions include, but are not limited to, any polynucleotide according to the invention (e.g., an antisense polynucleotide), any polypeptide according to the invention, an antibody specifically recognizing a polynucleotide or polypeptide according to the invention, a small molecule compound effective in modulating the expression of a polynucleotide according to the invention, and the like. Also contemplated are uses of compositions according to the invention for the manufacture of a medicament to ameliorate a symptom associated with a LEC- or BEC-associated disease or disorder.

Antibodies

Antibodies are useful for modulating the polypeptides of the invention due to the ability to easily generate antibodies with relative specificity, and due to the continued improvements in technologies for adopting antibodies to human therapy. Thus, the invention contemplates use of antibodies (e.g., monoclonal and polyclonal antibodies, single chain antibodies, chimeric antibodies, bifunctional/bispecific antibodies, humanized antibodies, human antibodies, and complementary determining region (CDR)-grafted antibodies, including compounds which include CDR sequences which specifically recognize a polypeptide of the invention), specific for polypeptides of interest to the invention. Preferred antibodies are human antibodies, such as those produced in transgenic animals, which are produced and identified according to methods described in WO93/11236, published Jun. 20, 1993, which is incorporated herein by reference in its entirety. Antibody fragments, including Fab, Fab′, F(ab′)2, and Fv, are also provided by the invention. The term “specific for,” when used to describe antibodies of the invention, indicates that the variable regions of the antibodies of the invention recognize and bind the polypeptide of interest at a detectably different, and greater, level that bind to other substances (i.e., able to distinguish the polypeptides of interest from other known polypeptides of the same family, by virtue of measurable differences in binding affinity, despite the possible existence of localized sequence identity, homology, or similarity between family members). It will be understood that specific antibodies may also interact with other proteins (for example, S. aureus protein A or other antibodies in ELISA techniques) through interactions with sequences outside the variable region of the antibodies, and in particular, in the constant region of the molecule. Screening assays to determine binding specificity of an antibody of the invention are well known and routinely practiced in the art. For a comprehensive discussion of such assays, see Harlow et al. (Eds.), Antibodies A Laboratory Manual; Cold Spring Harbor Laboratory; Cold Spring Harbor, N.Y. (1988), Chapter 6.

Non-human antibodies may be humanized by any method known in the art. A preferred “humanized antibody” has a human constant region, while the variable region, or at least a complementarity-determining region (CDR), of the antibody is derived from a non-human species. Methods for humanizing non-human antibodies are well known in the art. (see U.S. Pat. Nos. 5,585,089, and 5,693,762). Generally, a humanized antibody has one or more amino acid residues introduced into its framework region from a source which is non-human. Humanization can be performed, for example, using methods described in Jones et al. [Nature 321: 522-525, (1986)], Riechmann et al., [Nature, 332: 323-327, (1988)] and Verhoeyen et al. [Science 239:1534-1536, (1988)], by substituting at least a portion of a rodent CDR for the corresponding regions of a human antibody. Numerous techniques for preparing engineered antibodies are described, e.g., in Owens and Young, J. Immunol. Meth., 168:149-165 (1994). Further changes can then be introduced into the antibody framework to modulate affinity or immunogenicity.

The invention further provides a hybridoma that produces an antibody according to the invention. Antibodies of the invention are useful for detection and/or purification of the polypeptides of the invention.

Polypeptides and/or polynucleotides of the invention may also be used to immunize animals to obtain polyclonal and monoclonal antibodies which specifically react with the polypeptide. Such antibodies may be obtained using either the entire polypeptide or fragments thereof as an immunogen. The peptide immunogens additionally may contain a cysteine residue at the carboxyl terminus, and may be conjugated to a hapten such as keyhole limpet hemocyanin (KLH). Methods for synthesizing such peptides are known in the art, for example, as in R. P. Merrifield, J. Amer. Chem. Soc. 85:2149-2154 (1963); J. L. Krstenansky, et al., FEBS Lett. 211: 10 (1987). Monoclonal antibodies binding to the protein of the invention may be useful diagnostic agents for the immunodetection of the polypeptide. Neutralizing monoclonal antibodies binding to the polypeptide may also be useful therapeutics for both conditions associated with the polypeptide and also in the treatment of some forms of cancer where abnormal expression of the polypeptide is involved. In the case of cancerous cells or leukemic cells, neutralizing monoclonal antibodies against the polypeptide are useful in detecting and preventing the metastatic spread of the cancerous cells mediated by the polypeptide. In general, techniques for preparing polyclonal and monoclonal antibodies as well as hybridomas capable of producing the desired antibody are well known in the art (Campbell, A. M., Monoclonal Antibodies Technology: Laboratory Techniques in Biochemistry and Molecular Biology, Elsevier Science Publishers, Amsterdam, The Netherlands (1984); St. Groth et al., J. Immunol. 35:1-21 (1990); Kohler and Milstein, Nature 256:495-497 (1975)), the trioma technique, the human B-cell hybridoma technique (Kozbor et al., Immunology Today 4:72 (1983); Cole et al., in Monoclonal Antibodies and Cancer Therapy, Alan R. Liss, Inc. (1985), pp. 77-96).

Any animal (mouse, rabbit, and the like) which is known to produce antibodies can be immunized with a peptide or polypeptide of the invention. Methods for immunization are well known in the art. Such methods include subcutaneous or intraperitoneal injection of the polypeptide. One skilled in the art will recognize that the amount of the polypeptide encoded by an ORF of the invention used for immunization will vary based on the animal which is immunized, the antigenicity of the peptide and the site of injection. The protein that is used as an immunogen may be modified or administered in an adjuvant in order to increase the protein's antigenicity. Methods of increasing the antigenicity of a protein are well known in the art and include, but are not limited to, coupling the antigen with a heterologous protein (such as a globulin or β-galactosidase) or through the inclusion of an adjuvant during immunization.

For monoclonal antibodies, spleen cells from the immunized animals are removed, fused with myeloma cells, such as SP2/0-Ag14 myeloma cells, and allowed to become monoclonal-antibody-producing hybridoma cells. Any one of a number of methods well known in the art can be used to identify the hybridoma cell which produces an antibody with the desired characteristics. These include screening the hybridomas with an ELISA assay, Western blot analysis, or radioimmunoassay (Lutz et al., Exp. Cell Research. 175:109-124. 1988). Hybridomas secreting the desired antibodies are cloned and the class and subclass is determined using procedures known in the art (Campbell, A. M., Monoclonal Antibody Technology: Laboratory Techniques in Biochemistry and Molecular Biology, Elsevier Science Publishers, Amsterdam, The Netherlands (1984)). Techniques described for the production of single-chain antibodies (U.S. Pat. No. 4,946,778) can be adapted to produce single-chain antibodies to polypeptide of the invention.

For polyclonal antibodies, antibody-containing antiserum is isolated from the immunized animal and is screened for the presence of antibodies with the desired specificity using one of the above-described procedures. The invention further provides the above-described antibodies in detectably labeled form. Antibodies can be detectably labeled through the use of radioisotopes, affinity labels (such as biotin, avidin, and the like), enzymatic labels (such as horseradish peroxidase, alkaline phosphatase, and the like) fluorescent labels (such as FITC or rhodamine, and the like), paramagnetic atoms, and the like. Procedures for accomplishing such labeling are well-known in the art; for example, see Stemberger, L. A. et al., J. Histochem. Cytochem. 18:315. 1970; Bayer, E. A. et al., Meth. Enzym. 62:308 (1979); Engval, E. et al., Immunol. 109:129. 1972; and Goding, J. W. J. Immunol. Meth. 13:215. (1976).

The labeled antibodies of the present invention can be used for in vitro, in vivo, and in situ assays to identify cells or tissues in which a fragment of the polypeptide of interest is expressed. The antibodies may also be used directly in therapies or other diagnostics. The present invention further provides the above-described antibodies immobilized on a solid support. Examples of such solid supports include plastics such as polycarbonate, complex carbohydrates such as agarose and sepharose, and acrylic resins such as polyacrylamide and latex beads. Techniques for coupling antibodies to such solid supports are well known in the art (Weir, D. M. et al., “Handbook of Experimental Immunology” 4th Ed., Blackwell Scientific Publications, Oxford, England, Chapter 10 (1986); Jacoby, W. D. et al., Meth. Enzym. 34 Academic Press, N.Y. (1974)). The immobilized antibodies of the present invention can be used for in vitro, in vivo, and in situ assays as well as for immuno-affinity purification of the proteins of the present invention.

Computer-Readable Sequences

In one application of this embodiment, a nucleotide sequence of the present invention can be recorded on computer-readable media. As used herein, “computer-readable media” refers to any medium which can be read and accessed directly by a computer. Such media include, but are not limited to, magnetic storage media, such as floppy discs, hard disc storage medium, and magnetic tape; optical storage media such as CD-ROM; electrical storage media such as RAM and ROM; and hybrids of these categories such as magnetic/optical storage media. A skilled artisan can readily appreciate how any of the presently known computer-readable media can be used to create a manufacture comprising computer-readable medium having recorded thereon a nucleotide sequence of the present invention. As used herein, “recorded” refers to a process for storing information on computer-readable medium. A skilled artisan can readily adopt any of the presently known methods for recording information on a computer-readable medium to generate manufactures comprising the nucleotide sequence information of the present invention.

A variety of data storage structures are available to a skilled artisan for creating a computer-readable medium having recorded thereon a nucleotide sequence of the present invention. The choice of the data storage structure will generally be based on the means chosen to access the stored information. In addition, a variety of data processor programs and formats can be used to store the nucleotide sequence information of the present invention on computer readable medium. The sequence information can be represented in a word processing text file, formatted in commercially-available software such as WordPerfect and Microsoft Word, or represented in the form of an ASCII file, stored in a database application, such as DB2, Sybase, Oracle, or the like. A skilled artisan can readily adapt any number of data processor structuring formats (e.g., text file or database) in order to obtain computer readable medium having recorded thereon the nucleotide sequence information of the present invention. By providing the nucleotide sequence of SEQ ID NO: 1-30, 45, 47, 49 and 51 or a representative fragment thereof, or a nucleotide sequence at least 99.9% identical to SEQ ID NO: 1-30, 45, 47, 49 and 51 in computer-readable form, a skilled artisan can routinely access the sequence information for a variety of purposes. Computer software is publicly available which allows a skilled artisan to access sequence information provided in a computer-readable medium. The examples which follow demonstrate how software which implements the BLAST (Altschul et al., J. Mol. Biol. 215:403-410. 1990) and BLAZE (Brutlag et al., Comp. Chem. 17:203-207 (1993)) search algorithms on a Sybase system is used to identify open reading frames (ORFs) within a nucleic acid sequence. Such ORFs may be protein-encoding fragments and may be useful in producing commercially important proteins such as enzymes used in fermentation reactions and in the production of commercially useful metabolites.

As used herein, “a computer-based system” refers to the hardware means, software means, and data storage means used to analyze the nucleotide sequence information of the present invention. The minimum hardware means of the computer-based systems of the present invention comprises a central processing unit (CPU), input means, output means, and data storage means. A skilled artisan can readily appreciate that any one of the currently available computer-based systems are suitable for use in the invention. As stated above, the computer-based systems of the present invention comprise a data storage means having stored therein a nucleotide sequence of the present invention and the necessary hardware means and software means for supporting and implementing a search means. As used herein, “data storage means” refers to memory which can store nucleotide sequence information of the present invention, or a memory access means which can access manufactures having recorded thereon the nucleotide sequence information of the present invention.

As used herein, “search means” refers to one or more programs which are implemented on the computer-based system to compare a target sequence or target structural motif with the sequence information stored within the data storage means. Search means are used to identify fragments or regions of a known sequence which match a particular target sequence or target motif. A variety of known algorithms are disclosed publicly and a variety of commercially available software for conducting search means are and can be used in the computer-based systems of the present invention. Examples of such software includes, but is not limited to, MacPattern (EMBL), BLASTN and BLASTA (NPOLYPEPTIDEIA). A skilled artisan can readily recognize that any one of the available algorithms or implementing software packages for conducting homology searches can be adapted for use in the present computer-based systems. As used herein, a “target sequence” can be any nucleic acid or amino acid sequence of six or more nucleotides or two or more amino acids. A skilled artisan can readily recognize that the longer a target sequence is, the less likely a target sequence will be present as a random occurrence in the database. The most preferred sequence length of a target sequence is from about 10 to 100 amino acids or from about 30 to 300 nucleotide residues. However, it is well recognized that searches for commercially important fragments, such as sequence fragments involved in gene expression and protein processing, may be of shorter length.

As used herein, “a target structural motif,” or “target motif,” refers to any rationally selected sequence or combination of sequences in which the sequence(s) are chosen based on a three-dimensional configuration which is formed upon the folding of the target motif. There are a variety of target motifs known in the art. Protein target motifs include, but are not limited to, enzyme active sites and signal sequences. Nucleic acid target motifs include, but are not limited to, promoter sequences, hairpin structures and inducible expression elements (protein binding sequences).

Diagnostic Assays and Kits

The present invention further provides diagnostic assays, and related kits, for hyper- and/or hypo-proliferative disorders or diseases of endothelial cells such as LECs or BECs. These assays comprise methods to identify the presence or expression of one of the ORFs of the present invention, or homolog thereof, in a test sample, using a nucleic acid probe or an antibody according to the invention.

In general, methods for detecting a polynucleotide of the invention can comprise contacting a sample with a compound that binds to and forms a complex with, the polynucleotide for a period sufficient to form the complex, and detecting the complex, so that if a complex is detected, a polynucleotide of the invention is detected in the sample.

Such methods can also comprise contacting a sample under stringent hybridization conditions with nucleic acid primers that anneal to a polynucleotide of the invention under such conditions, and amplifying annealed polynucleotides, so that if a polynucleotide is amplified, a polynucleotide of the invention is detected in the sample.

In general, methods for detecting a polypeptide of the invention can comprise contacting a sample with a compound that binds to and forms a complex with the polypeptide for a period sufficient to form the complex, and detecting the complex, so that if a complex is detected, a polypeptide of the invention is detected in the sample. In detail, such methods comprise incubating a test sample with one or more of the antibodies or one or more of the nucleic acid probes of the invention and assaying for binding of the nucleic acid probes or antibodies to components within the test sample.

Conditions for incubating a nucleic acid probe or antibody with a test sample vary. Incubation conditions depend on the format employed in the assay, the detection methods employed, and the type and nature of the nucleic acid probe or antibody used in the assay. One skilled in the art will recognize that any one of the commonly available hybridization, amplification or immunological assay formats can readily be adapted to employ the nucleic acid probes or antibodies of the present invention. Examples of such assays can be found in Chard, T., An Introduction to Radioimmunoassay and Related Techniques, Elsevier Science Publishers, Amsterdam, The Netherlands (1986); Bullock, G. R. et al., Techniques in Inmunocytochemistry, Academic Press, Orlando, Fla. Vol. 1 (1982), Vol. 2 (1983), Vol. 3 (1985); Tijssen, P., Practice and Theory of immunoassays: Laboratory Techniques in Biochemistry and Molecular Biology, Elsevier Science Publishers, Amsterdam, The Netherlands (1985). The test samples of the present invention include cells, protein or membrane extracts of cells, or biological fluids such as sputum, blood, serum, plasma, or urine. The test sample used in the above-described method will vary based on the assay format, nature of the detection method and the tissues, and cells or extracts used as the sample to be assayed. Methods for preparing protein extracts or membrane extracts of cells are well known in the art and can be readily be adapted in order to obtain a sample which is compatible with the system utilized.

In another embodiment of the present invention, kits are provided which contain the necessary reagents to carry out the assays of the present invention. In one embodiment, the invention provides a compartment kit to receive, in close confinement, one or more containers which comprises: (a) a first container comprising one of the probes or antibodies of the present invention; and (b) one or more other containers comprising one or more of the following: wash reagents, reagents capable of detecting presence of a bound probe or antibody.

In detail, a compartment kit includes any kit in which reagents are contained in separate containers. Such containers include small glass containers, plastic containers or strips of plastic or paper. Such containers allows one to efficiently transfer reagents from one compartment to another compartment such that the samples and reagents are not cross-contaminated, and the agents or solutions of each container can be added in a quantitative fashion from one compartment to another. Such containers will include a container which will accept the test sample, a container which contains the antibody or antibodies used in the assay, containers which contain wash reagents (such as phosphate-buffered saline, Tris buffers, and the like), and containers which contain the reagents used to detect the bound antibody or probe. Types of detection reagents include labeled nucleic acid probes, labeled secondary antibodies, or in the alternative, if the primary antibody is labeled, the enzymatic, or antibody binding reagents which are capable of reacting with the labeled antibody. One skilled in the art will readily recognize that the disclosed probes and antibodies of the present invention can be readily incorporated into one of the established kit formats which are well known in the art.

EXAMPLES

Methods used in the examples are as follows:

Antibodies

Monoclonal antibodies against human VEGFR-3 (clone 2E11D11; see International Patent Application No. PCT/US02/22164, published as WO 03/006104), PAL-E (Monosan), CD31 (Dako), N-cadherin, VE-cadherin, β-catenin and plakoglobin and polyclonal rabbit anti-human podoplanin were used (Breiteneder-Geleff, S., et al., Am. J. Pathol. 154:385-394 (1999)); Mouse anti-human integrin α9 was provided by Dr. Dean Sheppard (University of California at San Francisco, San Francisco) and Dr. Curzio Rüegg (University of Lausanne Medical School, Lausanne, Switzerland). The fluorochrome-conjugated secondary antibodies were obtained from Jackson Immunoresearch.

Cell Culture and Transfection

Human amniotic epithelial cells were cultured in Med199 medium in the presence of 5% fetal calf serun. Human dermal microvascular endothelial cells were obtained from PromoCell (Heidelberg, Germany). Anti-Podoplanin antibodies, MACS colloidal super-paramagnetic MicroBeads conjugated to goat anti-rabbit IgG antibodies (Miltenyi Biotech, Bergisch Gladbach, Germany), LD and MS separation columns and Midi/MiniMACS separators (Miltenyi Biotech) were used for cell sorting according to the instructions of the manufacturer. The isolated cells were cultured on fibronectin-coated (10 μg/ml, Sigma, St. Louis, Mo.) plates as described (Mäkinen, T., et al., EMBO J. 20:4762-4773. 2001).

RNA Isolation, Northern Blotting and Microarray Analyses

Total RNA was isolated and DNAseI treated in RNeasy columns (Qiagen, Valencia, Calif.). ³²P-labeled probes for hybridization with the Atlas filters (Clontech) were prepared using 2-5 μg of total RNA according to the manufacturer's instructions with the exception that the probe was purified using Nick-25 columns (Pharmacia Biotech, Uppsala, Sweden). Following hybridizations and washes, the membranes were analyzed using a Fuji BAS 100 phosphoimager. For the Affymetrix® analysis, four independent BEC and LEC sample preparations and hybridizations were carried out using RNA extracted from four lots of cells isolated from different individuals. For the Affymetrix® expression analysis, 5 μg of total RNA was used for the synthesis of double-stranded cDNA using Custom SuperScript ds-cDNA Synthesis Kit (Invitrogen, Carlsbad, Calif.). Biotin-labeled cRNA was then prepared using the Enzo BioArrayTMHighYieldTMRNA Transcript Labelling Kit (Affymetrix, Santa Clara, Calif.), and the unincorporated nucleotides were removed using RNeasy columns (Qiagen, Valencia, Calif.). The hybridization, washing and staining of Human Genome 95Av2 microarrays (for Prox-1 experiments) and 9513-E microarrays, which mainly contain uncharacterized EST sequences, were done according to the instructions of the manufacturer (Affymetrix, GeneChip Expression Analysis Technical Manual). The probe arrays were scanned at 570 nm using an Agilent GeneArray® Scanner and the readings from the quantitative scanning were analyzed by the Affymetrix® Microarray Suite version 5.0 and Data Mining Tool version 3.0. For the comparison analyses, the hybridization intensities were calculated using a global scaling intensity of 100.

The differentially expressed sequences were used for searching EST contigs in the GenBank database of the National Center for Biotechnology Information and the National Library of Medicine. (NCBI/NLM), and open reading frames were predicted using the orf finder software available at NCBI/NLM. The SOSUI system was used for prediction of transmembrane helices and signal sequences from the protein sequences, and other protein domain architectures were analysed using Pfam (Protein families database of alignments and HMMs).

Immunofluorescence and Immunohistochemistry

The cells were cultured on coverslips, fixed with 4% paraformaldehyde, permeabilized with 0.1% Triton-X100 in phosphate-buffered saline (PBS) and stained with the primary antibodies. For integrin α9, staining live cells were incubated with the antibody for 15 minutes on ice before fixation. The cells were further stained with FITC- or TRITC-conjugated secondary antibodies. F-actin was stained using TexasRed-conjugated phalloidin (Molecular Probes, Eugene, Oreg.). Cells were counterstained with Hoechst 33258 fluorochrome (Sigma) and viewed using a Zeiss Axioplan 2 fluorescent microscope.

Normal human skin obtained after surgical removal was embedded in Tissue-Tek® (Sakura, The Netherlands), frozen and sectioned. The sections (6 μm) were fixed in cold acetone for 10 minutes and stained with the primary antibodies followed by peroxidase staining using Vectastain Elite ABC kit (Vector Laboratories, Burlingame, Calif.) and 3-amino-9-ethyl carbazole (Sigma, St. Louis, Mo.).

Example 1 Identification of Differentially Expressed Genes

Blood vascular and lymphatic endothelial cells (BEC and LEC, respectively) were isolated from cultures of human dermal microvascular endothelial cells using magnetic microbeads and antibodies against the lymphatic endothelial cell surface marker podoplanin (Breiteneder-Geleff, S., et al., Am. J. Pathol. 154:385-394 (1999); Makinen, T., et al., EMBO J. 20:4762-4773 (2001)). The purities of the isolated BEC and LEC populations were confirmed to be over 99% as assessed by immunofluorescence using antibodies against VEGFR-3 or podoplanin. The isolated cells were cultured for a couple of passages, and RNA was extracted from the cultures and used for hybridization with oligonucleotide microarrays containing sequences from about 12,000 known genes, ie., approximately ⅓ of the total number of all predicted human transcripts.

As expected, podoplanin, desmoplakin I/II and the macrophage mannose receptor, which are known lymphatic endothelial cell markers, were found specifically in the LECs. See, Breiteneder-Geleff, S., et al., Am. J. Pathol. 154:385-394 (1999); Ebata, N., et al., Microvasc. Res. 61:40-48. (2001); and Irjala, H., et al., J. Exp. Med. 194:1033-1041 (2001). Since these results were consistent with the known gene expression patterns in vivo and in vitro, further characterization of the gene expression profiles was carried out. When a reproducible signal log₂ ratio of 1.0 (twofold difference) was selected in the replicate analyses, over 400 genes were found to be differentially expressed between LECs and BECs. Some examples of the differentially expressed genes have been functionally annotated in Table 1 and a complete list of the differentially expressed genes is provided in Tables 2-4. A complete list of differentially expressed genes containing the GenBank accession numbers and the variation between the expression levels between independently harvested BECs and LECs (signal log₂ ratio ±s.d.) are provided in Tables 3 and 4. The microarray data were validated by Northern blotting or by immunofluorescence for 31 of the selected genes (see FIG. 1).

Each gene listed in Tables 3 and 4 is identified by a gene accession number which correlates to the sequence of the gene as found in a public genome database such as the GenBank database maintained by NCBI. These sequences are incorporated herein by reference. TABLE 1 Selected classes of genes differentially expressed in BECs and LECs. Blood vascular EC Lymphatic EC Adhesion molecules integrin alpha5 integrin alpha9* integrin β5, β4* integrin alpha1 ICAM-1*, ICAM-2 macrophage mannose receptor I* N-cadherin* selectin P, selectin E* protocadherin 42* CD44* EphrinB1* Cytoskeletal proteins vinculin desmoplakin I and II* claudin 7* adducin gamma actin, alpha 2 alpha-actinin-2 associated LIM profilin 2 protein* ECM proteins collagens 8A1*, 6A1*, 4A2/13A1*, Matrix Gla protein* 1A2* laminin* versican* proteoglycan 1 ECM modulation MMP-1, MMP-10, MMP-14* TIMP-3 uPA*, tPA* cathepsin C Receptor tyrosine VEGFR-1 (sVEGFR-1*) VEGFR-3* kinases Lyn and other protein Dyrk3 kinases Transcription factors STAT6* prox-1* TFEC* MEF2C* MAD-3* c-maf* HMGI-C* forkhead box M1 JUN* CREM GATA2 ear-3 Growth factors VEGF-C* Angiopoietin-2 Placenta growth factor Cytokines, chemokines IL-8*, IL-6* IL-7* and receptors stem cell factor* SDF-1b* Monocyte chemotactic protein 1 UFO/axl* CXCR4 CCRL2/CKRX* IL-4 receptor Cell cycle p27* Cdk-inhibitor p57KIP2* p21 cyclin-dependent kinase inhibitor 3, gadd45 CIP2 cyclin E2* cyclin B1, B2* Oxidative stress thioredoxin reductase beta* selenoprotein P* Other Neuropilin-1 podoplanin* HNMP-1* MRC OX2 endothelial cell protein C/APC Apolipoprotein D receptor Semaphorin 3A* Rnase A, pancreatic* fatty acid binding protein 4 TGF-β LITAF/Pig7* LTBP-2 IGFBP-2* metallothionein I, II, III piccolo* Cyclooxygenase 2* monoamine oxidase A clusterin/Apolipoprotein J neuronal pentraxin II* neuronal pentraxin I* Total 222 genes 187 genes Genes shown in bold were confirmed by Northern blotting or immunofluorescence, and those marked with an asterisk (*) were specifically expressed in only one of the two cell lineages.

TABLE 2 Known LEC-specific genes Accession numbers Gene Detection* starting EST possible gene CD36 = Af (S/4, 3) R20784 M98399 COL1/TSP receptor, fatty-acid transport H54254 protein beta1-syntrophin Af (S/4, 5) AA447177 L31529 collectin sub-family member 12 Af (S/4, 5) R74387 NM_030781 a disintegrin and metalloprotease Af (S/4, 3) AA147933 NM_003474 domain 12 cytotoxic T-lymphocyte- Af (S/4, 0) AI733018 NM_005214 associated protein 4 niban protein NM_022083 niban Af (S/3, 7) AA554814 NM_052966 protein multi-PDZ-domain-containing Af (S/3, 5) AI738919 NM_032622 protein, LNX MAGE-E1 protein Af (S/3, 2) AI435112 NM_030801 upstream stimulatory factor 1, Af (S/2, 6) AA701033 AB017568 USF1 (genomic match) hairy/enhancer-of-split related Af (NS/2, 6) R61374 NM_012258 with YRPW motif 1 alpha-2,8-polysialyltransferase Af (S/2, 5) AI422986 L41680 semaphorin 6A1 Af (S/2, 4) W21965 NM_020796 guanine nucleotide binding Af (S/2, 3) AA738022 protein (G prot), gamma 2 integral membrane protein 3 Af (S/2, 3) AA128019 NM_030926 similar to mouse glucocorticoid- Af (S/2, 0) AI678080 XM_070471 induced gene 1 YAP65 (Yes-associated protein of Af (NS/2, 0) AL048399 X80507 65 kDa MW) 17 kDa fetal brain protein Af (NS/1, 9) H92988 NM_022343 Kruppel-like factor 5 Af (S/1, 8) AI815057 NM_001730 calcitonin receptor-like, CGRP Af (S/1, 7) AI741128, NM_005795, L76380 type 1 receptor T94540 fibroblast growth factor 13, Af (NS/1, 7) AW014749 NM_004114 isoform 1A tetraspan NET-6 protein Af (NS/1, 6) W22687 NM_014399 ring finger protein 11 Af (S/1, 6) AL079648 BC020964 *Af = Affymetrix, S = specific for LEC, NS = nonspecific (also expressed in BEC), numbers represent log₂ ratio of the signal intensities between BEC and LEC

Example 2 Bec-Specific Expression of Genes Involved in Inflammation

Endothelial cells play an important role in several steps of the inflammatory response. They recruit leukocytes to inflammatory foci and specialized endothelial cells (high endothelial venules) are responsible for the homing of lymphocytes to the secondary lymphoid organs. In addition, endothelial cells modulate leukocyte activation and vice versa, and they can become activated by molecules secreted by the leukocytes. Consistent with their activation in cell culture, the BECs expressed high levels of pro-inflammatory cytokines and chemokines (stem cell factor, interleukin-8, monocyte chemotactic protein 1 (MCP-1)) and receptors (UFO/axl, CXCR4, IL-4R) see Table I. CXCR4 and its ligand, stromal cell-derived factor-1 (SDF-1), play important roles in the trafficking of normal lymphocytes, monocytes, and hematopoietic stem- and progenitor cell, targeted inactivation of either CXCR4 or SDF-1 results in impaired cardiogenesis, hematopoiesis and vascular development (Tachibana, et al., Nature 393:591-594. 1998). SDF-1b was mainly produced by the LECs, suggesting that this chemokine may be involved in LEC-initiated chemotaxis of the CXCR4-expressing cells. Moreover, the reciprocal pattern of expression of CXCR4 and SDF-1 on BECs and LECs suggest that the two cell types use these molecules for paracrine communication.

Example 3 Differences in Cell Adhesion, Cell-Cell Interaction and Cytoskeletal Molecules

The most striking differences detected between the BECs and LECs was the expression of genes involved in cytoskeletal and cell-cell or cell-matrix interactions (see Tables 3 and 4). For example, N-cadherin, which is involved in the interaction of endothelial cells with SMCs and pericytes (Gerhardt, et al., Dev. Dyn. 218:472-479. 2000), was detected specifically in BECs. This is consistent with the fact that the lymphatic capillaries are not ensheathed by SMCs. In immunostaining, N-cadherin was detected exclusively in the BECs, whereas VE-cadherin was present in both cell types (FIG. 2 a-d). The cytoplasmic domains of cadherins interact with β-atenin, plakoglobin (γ-catenin) and p120^(ctn), which link them to the actin cytoskeleton via α-actinin, vinculin, ZO-1, ZO-2 and spectrin (Provost, E. & Rimm, Curr Op. Cell Biol. 11:567-572. 1999). BECs expressed significantly higher levels of β-catenin (FIG. 2 e,f) and vinculin, whereas plakoglobin was mostly present on LECs (FIG. 2 g,h). Staining of LECs and BECs also revealed a strikingly different organization of the actin cytoskeleton. BECs displayed numerous stress fibers, which in LECs were almost totally absent, and instead a cortical distribution of actin was observed in LECs(FIG. 2 i,j).

Integrins are important mediators of cell adhesion (Giancotti & Ruoslahti, Science 285:1028-1032. 1999). They are transmembrane proteins consisting of two polypeptides, the α and β subunits. Their ectodomains bind extracellular matrix proteins while the cytoplasmic domains interact with the cytoskeleton and with proteins involved in signal transduction. Integrin α5, which acts as a subunit of the fibronectin receptor, mainly was expressed in BECs. By contrast, integrins α1 and α9, which provide subunits for the receptors for laminin and collagen and for osteopontin and tenascin, respectively, were expressed in LECs (FIG. 1 a and FIG. 2 k,l). In human skin, antibodies against integrin α9 stained lymphatic capillaries specifically, while blood vessel endothelia were negative (FIG. 2 m-o). In addition, integrin α9 was detected in arterial smooth muscle cells as previously reported (Palmer, et al., J. Cell Biol. 123:1289-1297. 1993). Interestingly, integrin α9 has been shown to be important for the normal development of the lymphatic system. Mice lacking integrin α9β1 develop respiratory failure due to the accumulation of a milky pleural (presumably lymphatic) effusion and die within 6 to 12 days after birth (Huang, et al., Mol. Cell Biol. 20:5208-5215. 2000).

BECs, but not LECs, produced both laminin and different types of collagens (Table 4). In co-culture these basement membrane components may be necessary for the adhesion and growth of the LECs (Makinen, T., et al., EMBO J. 20:4762-4773. 2001). In addition, many of the proteins involved in matrix degradation and remodeling, including several matrix metalloproteinases, tissue-type and urokinase plasminogen activator, as well as plasminogen activator inhibitor I were detected mainly in BECs, while the tissue inhibitor of matrix metalloproteinases-3 (TIMP-3) was detected mainly in LECs (Table 3 and FIG. 1). Unlike the other TlMPs, which are soluble, TIMP-3 is a component of the extracellular matrix. Recombinant TIMP-3 has been reported to inhibit endothelial cell migration and tube formation in response to angiogenic factors, and when expressed in a tumor model, it inhibited tumor growth most likely by preventing tumor expansion, release of growth factors from the extracellular matrix, or angiogenesis (Anand-Apte, et al., Biochemistry & Cell Biology 74:853-862. 1996).

Additional previously unknown genes were identified in the microarray as LEC-specific transcription factors or transmembrane proteins. See Tables 5 and 6. TABLE 5 Transcription Factors Identified Accession numbers possible Gene Detection* starting EST gene Homologous to Iroquois related Af (S/4, 2) AA936528 not cloned homeobox 2 from human (

similar to mouse odd-skipped Af (S/3, 3) AI809953 (19) related 1 zinc-finger TF PAC clone RP4-751H13 from Af (S/2, 3) AC004877 7q35-qter similar to mouse glucocorticoid- Af (NS/2) AI678080 XM_070471 induced gene 1 *Af = Affymetrix, S = specific for LEC, NS = nonspecific (also expressed in BEC), numbers represent log2 ratio of the signal intensities between BEC and LEC

TABLE 6 Transmembrane Proteins Identified Accession numbers Gene Detection* starting EST possible gene KIAA0626 Af (S/4, 7) AB014526 NM_021647 (14) KIAA0644 Af (S/3, 9) AB014544 NM_014817 (15) unknown protein Af (S/3, 5) AI333655 XM_059074 (16) hypothetical protein Af (NS/1, 8) AI733570 NM_024600 (862) FLJ20898 similar to Af (NS/1, 7) AA447940 AK055654, layilin, unnamed XM_084655 protein product hypothetical protein Af (NS/3, 2) AI681538 NM_022068 (860) FLJ23403 KIAA0062 D31887 XM_046677 (47) mesenchymal stem Af (S/1, 8) AW009871 NM_016647 (17) cell protein DSCD75 *Af = Affymetrix, S = specific for LEC, NS = nonspecific (also expressed in BEC), numbers represent log2 ratio of the signal intensities between BEC and LEC

Additionally, Tables 10 and 11 describe the known LEC genes identified and their accession numbers, and the differentially expressed genes and their accession numbers, respectively, while Table 12 describes other unknown proteins identified in the screen.

Example 4 Differential Regulation of LEC Genes by Prox-1

The mechanisms responsible for the lymphatic differentiation program were investigated. The Prox-1 homeobox transcription factor was found to be expressed specifically in LECs and targeted disruption of Prox-1 in mice was reported to result in the arrest of lymphatic vessel development (Wigle et al., Cell, 98:769-778. 1999). Despite the fact that the prox-1 gene was discovered nearly ten years ago, Prox-1 target genes have not been identified. To determine whether the homeodomain transcription factor Prox-1 contributes to the differentiated LEC and BEC phenotypes, the genes identified above were analyzed for expression in primary BECs and LECs, in the presence and absence of Prox-1 over-expression.

Adenovirus-mediated gene transfer of prox-1 in primary endothelial cells was used to induce gene expression in the BEC cells. In order to eliminate gene expression changes caused by adenoviral infection, AdLacZ (encoding β-galactosidase) was introduced into BECs as a control.

A prox-1 cDNA was amplified by RT-PCR using total RNA from human endothelial cells and the primers 5′-GCCATCTAGACTACTCATGAAGCAGCT-3′ (SEQ ID NO: 61) and 5′-GCGCAGAATTCGGCCCTGACCATGACAGCACA-3′ (SEQ ID NO: 62). The PCR product was cloned into the pAMC expression vector, producing N-terminally Myc-tagged Prox-1. The construct was then subcloned into pAdCMV to yield AdProx-1 for adenovirus production. AdProx-1 and AdLacZ virus stocks were produced as described (Laitinen et al., Hum. Gene Ther. 9:1481-1486. 1998). Adenovirally produced Prox-1 migrated with a molecular weight of about 85 kDa and it was also recognized by antibodies against a Prox-1 C-terminal peptide. Mutant Prox-1 N625A/R627A, (asparagine to alanine change at codon 625, arginine to alanine change at codon 627) was made using the QuikChange site-directed mutagenesis kit (Stratagene, La Jolla, Calif.) and the following primers: (SEQ ID NO: 63) 5′-CTCATCAAGTGGTTTAGCGCTTTCCGTAGTTTTACTAC-3′ and (SEQ ID NO: 64) 5′-GTAGTAAAACTCACGGAAGCGCTAAACCACTTGATGAG-3..

Human dermal microvascular endothelial cells, coronary artery endothelial cells (CAECs), saphenous vein endothelial cells (SAVECs), BECs and LECs were plated 24 hours before adenoviral infection at a density of 8,000 cells/cm² and infected for 1 hour in serum-free medium at 50-100 PFU/cell. At the end of the incubation period the cells were washed and then cultured in complete medium for 20-24 hours. Total RNA isolation and array hybridization were performed as described above.

Titration experiments showed that infection of human microvascular endothelial cells with AdProx-1 or AdLacZ led to nuclear expression of the adenovirus-encoded protein in >90% of the cells at 24 hours post-infection. To investigate the changes in gene expression induced by Prox-1, human cDNA filter arrays were used, which contain about 1,000 genes-known to be important for general cellular metabolism as wells as genes specifically implicated in the regulation of cardiovascular function or hematopoiesis. AdProx-1 up-regulated the expression of 28 LEC genes and down-regulated 63 BEC genes, (see Table 7 below), which was confirmed by Northern blotting for 10 of 11 selected genes. When compared with genes differentially expressed in LECs and BECs, 15 genes (i.e., about 30%) modulated by Prox-1 were found to be differentially expressed between cultured LECs and BECs, suggesting that Prox-1 is a major regulator of lymphatic endothelial cell identity. TABLE 7 Prox-1 Regulated LEC/BEC Genes ¹signal log Gene Accession numbers ratio ²s.d. LEC-specific induced by AdProx-1 (28 genes) cyclin E2 AF091433 NM_057735 4.95 1.17 cysteine and glycine-rich protein 2 U57646 NM_001321 4.58 0.36 Cdk-inhibitor p57KIP2 U22398 NM_000076 3.77 0.68 paternally expressed 10 AB028974 NM_015068 3.54 0.95 thromboxane A2 receptor D38081 NM_001060 2.32 0.13 B-myb X13293 NM_002466 2.11 0.28 retinoblastoma-associated protein HEC AF017790 NM_006101 1.86 0.13 cholesterol 25-hydroxylase AF059214 NM_003956 1.86 0.56 G protein-coupled receptor, family C, group 5, member B AC004131 1.83 0.32 thymidine kinase 1 M15205 NM_003258 1.80 0.39 CREM (cAMP responsive element modulator) S68134 NM_001881 1.78 0.30 alpha-actinin-2-associated LIM protein AF002282 NM_014476 1.77 0.42 desmoplakin (DPI, DPII) AL031058 1.74 1.03 MCM6 minichromosome maintenance deficient 6 D84557 NM_005915 1.72 0.06 erythrocyte membrane protein band 4.9 (dematin) U28389 NM_001978 1.71 0.25 GTP cyclohydrolase 1 U19523 NM_000161 1.61 0.04 KIAA0186 gene product D80008 NM_021067 1.47 0.11 cell division cycle 2 protein X05360 NM_001786 1.35 0.43 hypothetical protein from clone 643 AF091087 NM_020467 1.25 0.22 ubiquitin carrier protein E2-C U73379 NM_007019 1.23 0.12 mitotic checkpoint kinase Mad3L AF053306 NM_001211 1.22 0.47 V-Erba Related Ear-3 Protein HG3510-HT3704 1.20 0.20 glycogen phosphorylase (PYGL) AF046798 1.16 0.54 fms-related tyrosine kinase 4, VEGFR-3 X69878 NM_002020 1.10 0.00 BTB (POZ) domain containing 3 AB023169 NM_014962 1.10 0.08 SMC4 structural maintenance of chromosomes 4-like 1 AB019987 NM_005496 1.09 0.59 (yeast) high-mobility group protein 2 X62534 NM_002129 1.07 0.04 alpha topoisomerase L47276 1.04 0.49 BEC-specific suppressed by AdProx-1 (63 genes) neuropilin-1 AF016050 NM_003873 −3.99 0.42 ras-related C3 botulinum toxin substrate 2, RAC2 M64595 NM_002872 −3.87 0.47 tripartite motif-containing 22 X82200 NM_006074 −3.56 0.28 small inducible cytokine A2 (monocyte chemotactic protein M26683 NM_002982 −3.56 0.03 1) zinc finger protein 238 AJ223321 NM_006352 −3.08 0.13 uPA X02419 −3.05 0.02 transcription factor EC D43945 NM_012252 −3.04 0.08 RNase A, pancreatic D26129 NM_002933 −2.72 0.02 vitamin A responsive; cytoskeleton regulated AF070523 NM_006407 −2.51 0.6 interleukin 6 X04430 NM_000600 −2.42 0.63 Rho GDP dissociation inhibitor (GDI) beta X69549 NM_001175 −2.42 0.03 matrix metalloproteinase 14 X83535 NM_004995 −2.37 0.08 E3 ubiquitin ligase SMURF2 AA630312 NM_022739 −2.22 0.06 death receptor 6 AF068868 NM_014452 −2.16 0.61 protein C receptor, endothelial (EPCR) L35545 NM_006404 −2.09 0.14 hematopoietic and neural membrane protein (HNMP-1) U87947 NM_001425 −2.08 0.63 KIAA0836 AB020643 −2.07 0.44 chondroitin sulfate proteoglycan 2 (versican) X15998 NM_004385 −1.99 0.65 regulator of G-protein signaling 4 AI267373 NM_005613 −1.93 0.54 phosphofructokinase, muscle U24183 NM_000289 −1.93 0.11 IGF-II mRNA-binding protein 3 U97188 NM_006547 −1.9 0.23 neuronal cell adhesion molecule Nr-CAM/hBRAVO AB002341 NM_005010 −1.89 0.13 cell surface glycoprotein CD44 L05424 −1.84 0.12 plasminogen activator inhibitor-1 J03764 NM_000602 −1.83 0.33 AF1Q protein U16954 NM_006818 −1.79 0.23 Homo sapiens clone 24674 mRNA sequence AF070578 −1.76 0.01 nicotinamide N-methyltransferase U08021 NM_006169 −1.74 0.49 lactate dehydrogenase B X13794 −1.73 0.08 KIAA0537 gene product AB011109 NM_014840 −1.73 0.08 LIM domain protein X93510 NM_003687 −1.67 0.11 lymphocyte antigen 75, DEC-205 AF011333 NM_002349 −1.61 0.08 natural killer cell transcript 4 AA631972 NM_004221 −1.59 0.05 phospholipase A2 M72393 −1.58 0.41 R-ras M14949 −1.56 0.1 adenylyl cyclase-associated protein 2 N90755 NM_006366 −1.55 0.08 leupaxin AF062075 NM_004811 −1.53 0.3 signal transducer and activator of transcription 6 (STAT6) AF067575 −1.51 0.45 LYL-1 M22637 −1.51 0.14 selectin P M25322 NM_003005 −1.47 0.37 protein kinase, cAMP-dependent, catalytic, beta M34181 NM_002731 −1.43 0.49 TRAM-like protein D31762 NM_012288 −1.42 0.43 guanylate binding protein 2, interferon-inducible M55543 NM_004120 −1.41 0.51 intercellular adhesion molecule 2 X15606 NM_000873 −1.38 0.13 proteoglycan 1, secretory granule X17042 NM_002727 −1.35 0.47 tropomyosin 1 (alpha) Z24727 NM_000366 −1.32 0.1 fibroblast activation protein, alpha subunit U09278 NM_004460 −1.25 0.12 hypothetical protein DKFZp564D0462 AL033377 −1.25 0.23 mitogen-activated protein kinase-activated protein kinase 3 U09578 NM_004635 −1.2 0.35 amyloid beta (A4) precursor protein-binding U62325 −1.2 0.18 AXL receptor tyrosine kinase M76125 NM_001699 −1.19 0.3 integrin alpha 5 X06256 NM_002205 −1.18 0.02 prion protein (PrP) U29185 −1.18 0.07 TRAF family member-associated NFKB activator U59863 NM_004180 −1.17 0.13 annexin VI Y00097 NM_001155 −1.16 0.12 transcobalamin II L02648 NM_000355 −1.16 0.12 sushi-repeat-containing protein, X chromosome U61374 NM_006307 −1.13 0.09 bone morphogenetic protein 6 M60315 NM_001718 −1.13 0.39 hypothetical protein from clones 23549 and 23762 U90908 NM_021226 −1.1 0.6 retina cDNA randomly primed sublibrary, EST W28438 −1.09 0.36 TU3A protein AF035283 −1.06 0.29 keratin 7 AJ238246 NM_005556 −1.05 0.53 latent transforming growth factor beta binding protein 2 Z37976 NM_000428 −1.04 0.13 N-cadherin M34064 NM_001792 −1.02 0.12 cDNA DKFZp564J0323 (from clone DKFZp564J0323) AL049957 −1.01 0.22 ¹The change is expressed as the log₂ ratio. ²Standard deviation of the change in the expression level.

The ability of recombinant Prox-1 expression in BECs (where it is normally absent) to modify the transcriptional program of these cells towards the lymphatic endothlial cell phenotype was also investigated. The control, AdLacZ, did not significantly alter the expression of BEC- or LEC-specific transcripts as determined by oligonucleotide microarray analyses. By contrast, AdProx-1 increased expression of many LEC-specific mRNAs, such as VEGFR-3, p57Kip2, desmoplakin I/II and alpha-actinin-associated LIM protein (see Table 8). Suprisingly, Prox-1 also suppressed the expression of about 40% of genes characteristically expressed in BECs, such as the transcription factor STAT6, the UFO/axl receptor tyrosine kinase, neuropilin-1 (NRP-1), monocyte chemoattractant protein-1 (MCP-1) and integrin α5 (see Table 7 and Table 8). These gene expression results are in agreement with the in vivo studies of lymphatic vessels. For example, VEGFR-3 and desmoplakin I/II are found in the lymphatic endothelium (Ebata et al., Microvasc. Res. 61:40-48. 2001; Kaipainen et al., Proc. Natl. Acad. Sci. U.S.A. 92: 3566-70. 1995), and the VEGR co-receptor NRP-1, which was suppressed by Prox-1 in the BECs, was found to be expressed in blood vessels, but not in lymphatic vessels in mouse skin. TABLE 8 Examples of LEC- and BEC-specific genes regulated by Prox-1 LEC-specific, up-regulated BEC-specific, down-regulated Adhesion molecules Integrin alpha 5 ICAM-2 CD44 Nr-CAM P-selectin Cytoskeletal proteins Desmoplakin I and II leupaxin alpha-actinin-2 associated LIM protein ECM proteins versican proteoglycan 1 ECM proteins versican proteoglycan 1 ECM modulation MMP-14 uPA PAI-I Receptor tyrosine kinases VEGFR-3 UFO/axl Transcription factors CREM STAT6 ear-3 Cytokines, chemokines TFEC and receptors IL-6 MCP-1 Cell cycle control p57Kip2 cyclin E2 Other cholesterol 25-hydroxylase Neuropilin-1 thromboxane A2 receptor endothelial cell protein C receptor Total 28 genes 63 genes (19% of LEC-specific genes) (38% of BEC-specific genes) Genes shown in bold were confirmed by Northern blotting or RT-PCR.

In order to determine whether the Prox-1-induced changes in gene expression were cell-type specific, changes in gene expression after AdProx-1 or AdLacZ infection were analyzed in additional endothelial cell types, i.e., coronary artery endothelial cells (CAECS) and saphenous vein endothelial cells (SAVECs), as well as a non-endothelial cell type, i.e., amniotic epithelial cells (AEC). In all of these cell types, AdProx-1 strongly up-regulated Cyclins E1 and E2, Histone H2B, and PCNA. However, AdProx-1 induced VEGFR-3 expression only in CAECs and SAVECs, and not in AECs.

These results are consistent with the lack of lymphatic differentiation in Prox-1-deficient embryos. Interestingly, the expression of Prox-1 in primary endothelial cells leads to up-regulation of VEGFR-3 receptor tyrosine kinase, which is specific for the lymphatic endothelium after midgestation and is essential for proper lymphatic growth and function (Karkkainen and Petrova, Oncogene 19:5598-5605. 2000). For example, inactivating mutations of VEGFR-3 in humans and mice lead to lymphatic hypoplasia and lymphedema (Jeltsch et al., Science 276:1423-1425. 1997; Karkkainen et al., Nat. Genet., 25:153-159. 2000; Karkkainen et al, Trends Mol. Med. 7:18-22. 2001). The results described above therefore suggest that the up-regulation of VEGFR-3 expression by Prox-1 is one of the key pathways involved in the establishment of lymphatic endothelial cell identity and also suggest that the distinct phenotypes of cells in the adult vascular endothelium are plastic and sensitive to transcriptional reprogramming, which is useful in the therapeutic methods of the invention affecting endothelial cells.

Example 5 Ex-vivo Cell Stimulation and Gene Therapy for Lymphedema with AdProx-1 Transfected Cells

The ability of Prox-1 to regulate genes specifically involved in LEC development provides a means for treatment of individuals exhibiting a LEC disorder or condition resulting from either an increase or decrease in LEC gene expression levels. Prox-1 upregulation is useful in promoting LEC development as a treatment for LEC disorders characterized by an under-developed lymphatic system of a condition characterized by a risk of wider-development such as lymphedema. Conversely, Prox-1 inhibition is useful in downregulating LEC development as a treatment for LEC disorders characterized by an over-developed lymphatic system such as lymphedema. It is known in the art that ex vivo transfection of cells and subsequent transfer of these cells to patients is an effective method to upregulate in vivo levels of the specific gene transferred and to provide relief from a disease resulting from under-expression of the gene(s) (Gelse et al., Arthritis Rheum. 48:430-41. 2003; Huard et al, Gene Ther 9:1617-26. 2002; Kim et al., Mol. Ther. 6:591-600 2002).

To develop a therapy for treating irregularities of LEC development, endothelial cells, such as CAECs, SAVECs, LECs or BECs, are isolated from individuals experiencing an LEC disorder (e.g. lymphedema) and then placed in an appropriate culture medium (see above) to promote the growth and viability of the cells. The cells are then transfected as described with the AdProx-1 vector as described above to initiate LEC differentiation of the non-LECs in vitro and to promote growth of the LECs in culture. These transfected cells are then transferred into an affected patient in therapeutically effective numbers to promote LEC expansion in vivo. In preferred embodiments, the manipulated cells are autologous cells. These cells are delivered by one or more administrations typically involving injection. The cells are delivered at a local site of an LEC disease or disorder such as lymphedema or systemically.

Addition of the Prox-1 transfected cells to patients with lymphedema provides supplementary LECs that are incorporated into the lymphatic network to promote lymphatic development and effectuate lymph clearance to relieve the symptoms of lymphedema. It is contemplated that a method comprising AdProx-1 transfection into endothelial cells and administration of transfected cells is useful in the treatment of any disease characterized by an alteration in LEC numbers or activity, such as lymphedema, lymphangioma, lymphangiomyeloma, lymphangiomatosis, lymphangiectasis, lymphosarcoma, and lymphangiosclerosis. Additionally, such methods are useful in ameliorating a symptom (e.g., lymph-induced swelling in the case of lymphedema) associated with such diseases.

Example 6 Characterization of LEC-Specific Genes

LEC-specific genes were further analyzed using a subtraction library between the LEC and BEC genes. To construct the library, total RNA was isolated as previously described and 5 μg of total RNA was pre-amplified using a SMART™ PCR cDNA synthesis kit (BD Biosciences Clontech). After RsaI-digestion, PCR-Select cDNA subtraction was carried out in both directions, resulting in selective amplification of differentially expressed sequences, and subtracted LEC and BEC cDNA libraries were prepared (BD Biosciences Clontech). Subtractive hybridization was performed with a 1 (tester): 30 (driver) ratio in both directions and subtracted CDNA pools were amplified by PCR. Forty ng of the purified PCR-amplified product were cloned into the pAtlas vector (PUC-based vector) for the construction of subtracted libraries, although a number of other vectors could be used in the construction, as would be known in the art.

Differential screening of the subtracted LEC-specific library was carried out as described in the PCR-Select Differential Screening Kit User Manual (BD Biosciences Clontech). The LEC-specific subtracted library was plated and individual bacterial clones were picked and grown. After DNA extraction, the inserts were amplified by PCR and used for sequencing. An aliquot of each PCR-amplified insert was also arrayed onto a nylon membrane and used for hybridization with ³²P-labeled cDNA probes. The results from the hybridizations with subtracted LEC-specific (tester) and subtracted BEC-specific (driver) cDNA probes were used for the differential expression analyses.

BLAST (The Basic Local Alignment Search Tool) was used to compare the sequences against nucleotide, protein and EST sequence databases. For unknown sequences, EST contigs were searched and open reading frames were predicted using ORF finder. Protein domain architectures were analyzed using Pfam (Protein families database of alignments and HMMs) and Smart (Simple Modular Architecture Research Tool).

The nucleotide sequences of clones that were differentially expressed in LECs versus BECs were analyzed in the manner described above. Several of the EST or unknown gene fragments detected in the first screen have been investigated further to determine their sequence similarities to known gene sequences and to identify any open reading frames and functional domain similarities. The results are collected in Table 9. TABLE 9 Clone designation Human Genome KIAA Designation # Expected Gene and (SEQ ID NO) EST Accession # and (SEQ ID NO) Function LE000100001_A06 AB014526 NM_021647 KIAA0626 Ig domain motif, (SEQ ID NO: 61) SEQ ID NO: 14 likely cell adhes

function LE0000100050_A01 AB014544 NM_014817 KIAA0644 Leucine rich moti

(SEQ ID NO: 59) SEQ ID NO: 15 cell adhesion LE0000100055_H05 activity AI333655 XM_059074 no KIAA, Leucine rich designated hLyrp repeats, cell SEQ ID NO: 16 adhesion protein AI681538 NM_016647 SEQ ID NO: 17 Similar to mesenchymal stem cell protein AA447940 XM_084655 SEQ ID NO: 45 similar to layili likely cell adhes function LE000100017_C02 XM_046677 D31887 KIAA0062 Zinc transporter (SEQ ID NO: 55) SEQ ID NO: 47 motif, metal ion transport LE0000100049_E10 XM_047672 XM_047672 KIAA1673 RNA-binding regio LE0000100054_F09 SEQ ID NO: 26 similar to RNA LE0000100056_F07 binding protein SEQ ID NOs: LE0000100053_A06 AI761647 NM_015147 KIAA0582 SEQ ID NO: 56 SEQ ID NO: 49 LE0000100055_G10 D14657 NM_014736 KIAA0101 LE0000100046_C12 SEQ ID NO: 51 SEQ ID NOs: 57-58

Several of the LEC-specific genes have been found to correspond to KIAA gene sequences, which are large nucleotide EST clones encoding unknown human proteins. (Kazusa DNA Research Institute, 1532-3, Yana Kisarazu, Chiba, 292-0812, Japan). These LEC-specific genes were further analyzed in several available databases to determine the existence of species homologs and the percent similarity in these homologs and also to reveal amino acid sequences that demonstrate similarity to conserved protein domains.

Analyses of the LEC clone sequences was performed using the HomoloGene database maintained by the U.S. National Center for Biotechnology Information offered by the National Institutes of Health to determine species homologs and orthologs and their percent similarity to the newly isolated human LEC-specific genes. Analyses of the sequences was performed using a resource of curated and calculated homologs for genes as represented by UniGene or by annotation of genomic sequences, generally comparing EST and mRNA sequences from UniGene, as well as transcripts extracted from annotated genomic sequences. (Zhang, et al., J. Comp. Biol. 7:203-14. 2000). The best match for a nucleotide sequence in one organism to a nucleotide sequence in a second organism is based on the degree of similarity between the two sequences, with a minimum alignment of 100 base pairs. The similarity between the two sequences was determined by an alignment score. The alignment score for a sequence pair is the sun of the similarity scores of the sections of the two sequences that aligned.

HomoloGene analyses indicate that human LEC genes corresponding to KIAA0626, KIAA0644, and KIAA0062, are homologous to EST and unknown gene sequences in mouse (all), rat (KIAA0062, KIAA0644), cow (KIAA0062), pig (KIAA0626, KIAA0644) and Xenopus (KIAA0644). The clones showed approximately 80% (±3%) similarity to the genes identified as homologs by HomoloGene, with KIAA0644 demonstrating as high as 86% homology to pig EST sequence BE233028.1 and as low as 72% similarity to an X. laevis gene.

Analyses of the LEC genes using Pfam comparison revealed that nucleotide sequences corresponding to KIAA0626 (SEQ ID NO: 14), KIAA0644 (SEQ ID NO: 15), hLyrp (SEQ ID NO: 16), XM_(—)084655 (SEQ ID NO: 45) and KIAA0062 (SEQ ID NO: 47), showed nucleotide sequence motifs characteristic of encoded transmembrane domains, indicating that the corresponding polypeptides (whose amino acid sequences are set out in SEQ ID NOS: 31, 32, 33, 46 and 48, respectively) are expressed on the cell surface. KIAA1673, KIAA0582 and KIAA0101 do not demonstrate an apparent transmembrane domain and are expected to be cytoplasmic or nuclear proteins. Tissue expression assayed by Northern blot reveals that KIAA0101 is detectable in kidney, thymus, colon and small intestine while KIAA0582 is expressed strongly in heart, skeletal muscle, and ovary, less in kidney and placenta, and more weakly in brain, lung, thymus, small intestine and prostate.

Northern blot analysis of the KIAA0626 transcript indicates that KIAA0626 is expressed specifically in LEC and is found in heart, skeletal muscle and kidney. In situ analysis demonstrates KIAA0626 expression in mouse embryonic day 11 (E11) embryos in the intersomitic tissue and pericytes surrounding the blood vessels, and in the yolk sac vessels, endothelial cells and in the surrounding pericytes. The polynucleotide sequence of KIAA0626 (SEQ ID NO: 14) encodes a 409 amino acid (409 aa) protein (SEQ ID NO: 31) possessing a signal sequence (at amino acids 1-29), an Ig superfamily domain (approximately aa 61-127), a short transmembrane region ( about aa 153-175) and a long 234-amino-acid cytoplasmic domain from about amino acids 176-409. The presence of an Ig domain is expected to assist in binding of the protein to its ligand while the long cytoplasmic domain indicates that KIAA0626 may be involved in intracellular signaling in LECs.

KIAA0644 (SEQ ID NO: 15) is detected by Northern blot analysis primarily in heart and brain tissue. In situ assay of E10 mouse embryos shows KIAA0644 expression throughout the embryo. The KIAA0644 polynucleotide encodes a 811-amino-acid polypeptide (SEQ ID NO: 32) demonstrating a total of 13 leucine rich regions. Leucine-rich regions comprise a short sequence motif of approximately 20-28 amino acids which are present in proteins functioning as cell-adhesion and receptor molecules. Leucine-rich regions, designated below as LRRNT and LRRCT are often flanked by cysteine-rich domains. The KIAA0644 protein contains a leucine-rich N-terminal region (LRRNT: aa 26-54), 11 internal leucine-rich regions (LRR1: aa84-107, LRR2: aa108-131, LRR3: aa132-155, LRR4: aa156-179, LRR5: aa180-203, LRR6: aa204-223, LRR7: aa230-253, LRR8: aa254-277, LRR9: aa278-301, LRR10: aa302-325, and LRR11: aa326-349) and a C-terminal leucine-rich region (LRRCT) from about amino acids 359-404. The KIAA0644 transmembrane domain spans approximately amino acids 696-718, leaving a cytoplasmic domain of about 95 amino acids, from aa719-8 11. The leucine-rich regions of the KIAA0644 gene implicate it in protein-protein interactions characteristic of cell-adhesion or ligand binding.

The hLyrp (SEQ ID NO: 16) mRNA is detectable in skeletal muscle tissue and is localized by in situ hybridization to the lymphatic vessels when compared to Prox-1 staining in E11 and yolk sac of mouse embryos. Similar to KIAA0644, the hLyrp protein (SEQ ID NO: 33) contains a series of leucine-rich regions beginning at the leucine-rich N-terminal region (LRRNT: aa27-55) extending through 5 internal leucine-rich regions (LRR1: aa57-80, LRR2: aa81-104, LRR3: aa105-128, LRR4: aa129-153, LRR5: aa154-176) and ending with a C-terminal leucine-rich region (LRRCT) from approximately aa186-240. The hLyrp polypeptide also contains a transmembrane domain from amino acids 249-272, leaving a short cytoplasmic domain of 22 amino acids. The presence of several consecutive-leucine-rich regions in the hLyrp polypeptide indicates that the polypeptide functions as a cell-adhesion molecule and/or a cell surface receptor.

Several additional sequences shown in Table 3 were isolated with full-length mRNA sequences which are expressed specifically in LECs. Domain prediction of these sequences indicates that KIAA0711 (SEQ ID NO: 81 and 82) contains a BPB/POZ domain spanning approximately amino acids 171-269, this domain is expected to function in protein-protein interactions. POZ domains appear in transcriptional co-factors such as zinc-finger proteins that mediate transcriptional repression and interact with components of histone deacetylase complexes. KIAA0711 also has three Kelch repeats, spanning amino acids 386-437, 439-480, and 484-525, and Kelch motifs have been implicated in the formation of beta sheet structures. Additionally, KIAA0711 mRNA is expressed in a variety of tissues. From highest expression levels to lowest, KIAA0711 mRNA is found in brain and kidney; liver; spleen; lung; ovary, pancreas and heart; smooth muscle and testis. Because this expression pattern was obtained from a single run of RT-PCR ELISA, the expression profile has a chance to include significant run-to-run variations. Accordingly, the expression profiles are most suitable for screening genes for tissue-specific expression on a qualitative level. If more accurate quantitative expression profiles are required, more statistically reliable approaches should be employed (e.g., multiple RT-PCR-ELISA measurements, DNA chip analyses, RNA blot analyses, and the like).

Domain mapping of the sequence corresponding to cDNA DKFZp5640222 (SEQ ID NO: 93) indicates the presence of an N-terminal signal peptide (amino acids 1-23), two internal repeat domains and:an olfactomedin domain (amino acids 361-616), which is detected in proteins such as myocilin, pancortin, and latrophilin. Mutations in the OLF domain-of myocilin are associated with glaucoma

Domain mapping of KIAA1233 (SEQ ID NO: 111) indicates that the KIAA sequence contains six thrombospondin type I repeats, which are found in extracellular matrix proteins and are implicated generally in cell-cell interactions, and more specifically in the complement pathway, in the inhibition of angiogenesis, and in apoptosis. KIAA1233 also contains three immnunoglobulin C-2 type domains, similar to many glycoproteins. Proteins possessing both thrombospondin repeats and immunoglobulin domains are also involved in intracellular interactions, such as cell-adhesion and apoptosis. From highest expression levels to lowest, KIAA1233 mRNA is found in the spinal cord; heart, general brain, lung, liver, kidney, pancreas, various regions of the brain (amygdala, corpus callosum, caudate nucleus, hippocampus, substantia nigra, thalamus, and subthalamic nucleus) and fetal liver; fetal brain; spleen; and testis.

The KIAA0846 (SEQ ID NO: 188) protein contains motifs found in guanine nucleotide exchange factors and is thus probably an intracellular protein, perhaps a signaling protein. KIAA0846 also exhibits two EF-hand motifs found in signalling proteins (e.g. calmodulin, S100B), which undergo a calcium-dependent conformational change and are also found in buffering/transport proteins. From highest expression levels to lowest, KIAA0846 mRNA is found in kidney; heart, brain and lung; liver, spleen and ovary; pancreas, smooth muscle and testis.

Protein FLJ13110 (SEQ ID NOS: 207 and 208) exhibits a TB2/DP1, HVA22 family protein domain and two short transmembrane regions (amino acids 4-22 and 43-65 of SEQ ID NO: 207). The HVA22 family includes members from a wide variety of eukaryotes, including the TB2/DP1 (deleted in severe familial adenomatous polyposis) protein which is deleted in severe forms of familial adenomatous polyposis, an autosomal dominant oncological inherited disease.

The LEC-specific gene screen also identified protein KIAA0937 (SEQ ID NOS: 211 and 212). KIAA0937 contains WWE domains (from approximately amino acids 30-112, and 113-189 of SEQ ID NO: 211) which is named after three of its conserved residues and is predicted to mediate specific protein-protein interactions in ubiquitin and ADP ribose conjugation systems. KIAA0937 is also predicted to contain a zinc finger domain (from amino acids 443-501 of SEQ ID NO: 211) and is expected to be an intracellular transcription factor. From highest expression levels to lowest, KIAA0937 mRNA is found in the spinal cord; the subthalanic nucleus and cerebellum of the brain; the brain in general (including the amygdale, corpus callosum and fetal brain) and ovary; fetal liver, heart, lung, kidney, spleen and parts of the brain (caudate nucleus and hippocampus); testis and pancreas; and smooth muscle.

KIAA0952 (SEQ ID NO: 241 and 242) contains a Broad-Complex, Tramtrack and a Bric-a-brac domain, also known as a POZ (poxvirus and zinc finger) domain. These domains are known to be protein-protein interaction domains found at the N-termnini of several C2H2-type transcription factors, as well as Shaw-type potassium channels. The known structure of these domains reveals a tightly intertwined dimer formed via interactions between an N-terminal polypeptide strand and helix structures.

The protein designated KIAA0429 (SEQ ID) NOS: 391 and 392) is similar to metastasis suppressor protein and contains an actin-binding WH2 domain from approximately amino acids 467-484, as well as a proline-rich region from amino acids 348-466.

Protein FLJ23403 (amino acid sequence, SEQ ID NO:859; polynucleotide sequence, SEQ ID NO:860) shows approximately 85% homology to an unknown mouse protein (GenBank Acc. No. XM_(—)129000) and contains a series of four transmembrane domains spanning amino acids 44-66, 86-108, 115-137 and 452-474.

Additional LEC-specific, upregulated genes include previously unidentified proteins KIAA0186 (SEQ ID NOS: 221 and 222), KIAA0513 (SEQ ID NOS: 235 and 236) and the protein designated FLJ13910 (SEQ ID NOS: 293 and 294).

The manipulation of lymphatic endothelial-cell-specific molecules is expected to be applicable to treatments of LEC diseases disorders associated with tissue edemas. Without wishing to be bound by theory, manipulation of such molecules is expected to modulate endothelial cell-cell or cell-matrix protein interactions or to affect transendothelial transport thereby altering the state of fluid transport across the lymphatic vessel wall. Further, such molecules provide targets for the delivery of therapeutic compounds, such as growth factors, mitogens, and the like, as well as cytostatic or cytotoxic agents known in the art. These therapeutic compounds are targeted to such cells by associating a therapeutic agent with, e.g., a binding partner (such as an antibody) of the LEC surface marker. The transmembrane proteins identified herein, in particular the leucine-rich proteins, also provide useful targets for modulating cell adhesion events integral to lymph clearance.

Example 7 Microarray Analysis to Detect LEC- and Lymph-Related Disorders

The LEC-specific genes identified herein are useful in the detection of LEC in vivo and in determining the extent of the lymphatic vasculature in a sample. The LEC-specific genes are also expected to be useful in diagnosing lymphedema and other LEC-related disorders.

Another aspect of the invention is a composition comprising a plurality of polynucleotide probes for use in detecting gene expression pattern(s) characteristic of particular cell type(s) and for detecting changes in the expression pattern of a particular cell type, e.g., lymphatic endothelial cells. The term “polynucleotide probe” is used herein to refer to any one of the nucleic acid sequences listed in SEQ ID NO: 1-30, 45, 47, 49 and 51, or any fragment thereof or a nucleic acid sequence encoding an amino acid sequence listed in SEQ ID NOS: 31-44, 46, 48, and 50, or a fragment thereof. Preferably, the fragment is at least 10 nucleotides in length; more preferably, it is at least 20 nucleotides in length. Such a composition is employed for the diagnosis and treatment of any condition or disease in which the dysfunction or non-function of lymphatic endothelial cells is implicated or suspected. In one embodiment, the present invention provides a composition comprising a plurality of polynucleotide probes, wherein at least a subset of the polynucleotide probes comprises at least a portion of an expressed gene isolated from a population of LEC-specific genes identified above. Also contemplated is a composition comprising a plurality of polynucleotide probes, with at least a subset of such probes each comprising a unique sequence selected from the group of SEQ ID NOs: 1-30, 45, 47, 49 and 51. Preferably, the composition comprises a subset of at least 3 polynucleotides, each having a different sequence selected from the group of SEQ ID NOs: 1-30, 45, 47, 49 and 51. Also preferred are compositions comprising at least 5, at least 7, at least 9, at least 15, at least 20, or at least 25 distinct polynucleotides having sequences selected from the group of SEQ ID NOs: 1-30, 45, 47, 49 and 51.

The composition is particularly useful as a set of hybridizable array elements in a microarray for monitoring the expression of a plurality of target polynucleotides. The microarray comprises a substrate and the hybridizable array elements. The microarray is used, for example, in the diagnosis and prognosis of a disease derived from aberrant lymphatic endothelial cell activity, such as lymphedema, lymphangioma, lymphangiomyeloma, lymphangiomatosis, lymphangiectasis, lymphosarcoma, and lymphangiosclerosis. Compositions may be useful in identifying more than one cell type and may be useful in the diagnosis and prognosis of more than one disease, disorder or condition. Further, useful information is obtained from those probes yielding a signal and from those probes not yielding a signal.

A polynucleotide comprising the sequence of any one of SEQ ID NOS: 1-30, 45, 47, 49 and 51 may be used for the diagnosis of conditions or diseases with which the abnormal expression of any one of the genes encoded by SEQ ID NOS: 1-30, 45, 47, 49 and 51 is associated. For example, a polynucleotide comprising any one of the sequences set forth in SEQ ID NOS: 1-30, 45, 47, 49 and 51 may be used in hybridization or PCR assays of fluids or tissues (e.g.,.obtained from biopsies) to detect abnormal gene expression in patients with lymphedema or another lymph-associated disease. In addition, a polynucleotide comprising a sequence encoding any of the amino acid sequences set forth in SEQ ID NOS: 31-44, 46, 48 or 50 is useful for the diagnosis of conditions or diseases associated with aberrant expression of a polypeptide having any one of those amino acid sequences. Fragments comprising at least 10 nucleotides are also useful in these diagnostic methods.

Expression profiles may be generated using the compositions of the invention comprising SEQ ID NOs: 1-30, 45, 47, 49 and 51. The expression profile generated from the microarray is used to detect changes in the expression of genes implicated in disease.

Example 8 Transcription Factors in BECs and LECs

Transcription factors preferentially expressed in the LECs included the zinc finger factor c-maf and the MADS-family transcription factor MEF2C (FIG. 1). Targeted mutagenesis of MEF2C leads to embryonic death at E9.5-10 due to defects in the remodeling of the primary vasculature and abnormal endocardiogenesis (Bi, et al., Dev. Biol. 211:255-267. 1999). MEF2C has been reported to bind the transcription factor Sox18 and to potentiate its activity in endothelial cells (Hosking, et al., Biochem. Biophys. Res. Commun. 287:493-500. 2001). Mouse pups with a homozygous mutation in Sox18 that disrupts the MEF2C complex develop chylous ascites in some genetic backgrounds (Pennisi, D., et al., Nat. Genet. 24:434-437. 2000), suggesting that both proteins may be involved in the regulation of lymphatic development. In line with this hypothesis, RT-PCR analysis of MEF2C^(−/−) embryos showed decreased VEGFR-3 expression (Bi, et al., Dev. Biol. supra).

The STAT6 transcription factor, which is activated in response to IL-4, was expressed specifically in the BECs. Consistent with this observation, the results herein show that the IL-4 receptor was expressed preferentially in BECs, as were some of the IL-4 target chemokines and receptors such as MCP-1 and CXCR4. VEGF stimulation and activation of VEGFR-2 is also known to lead to STAT6 phosphorylation and activation in endothelial cells (Bartoli, et al., J. Biol. Chem. 275:33189-33192. 2000). The absence of STAT6 in LECs, therefore, suggests that the downstream signaling pathways of VEGFR-2 differ in BECs and LECs. Expression patterns of other transcription factors are shown in Table 5.

Example 9 Sox18 and Hereditary Lymphedema

Expression of the transcription factor MEF2C is upregulated in LECs. Sox18 (SEQ ID NO: 53, and encoding SOX18, SEQ ID NO: 54), which was reported to interact with MEF2C in mice, was also shown to play a potential role in lymphatic endothelial cell development. To investigate the role of Sox18 in human lymphedema, the correlation of human Sox18 mutants with human hereditary lymphedema was investigated.

The SOX proteins, homologs of the family of SRY transcription factors, are ubiquitous transcription factors which contain a putative high-mobility-group (HMG) DNA binding domain. (Wegner, M., Nucl. Acids Res. 27:1409-20. 1999). SOX proteins bind their DNA targets at a heptameric SOX consensus binding sequence [5′-(A/T)(A/T)CAA(A/T)G-3′] (Pennisi et al., Mol. Cell Bio. 20:9331-36. 2000) and generally bind DNA in the minor groove rather than the major groove of the double helix, which results in transcriptional regulation of the target gene. SOX proteins may also be involved in recruiting other DNA binding proteins to a DNA-protein complex, thereby assisting in transcription regulation (Wegner, supra). SOX18 shares homology with both SOX7 and SOX17, all members of the Group F Sox genes.

SOX18 is involved in vascular development and has been localized to the developing cardiovascular system and sites of angiogenic activity. Mice homozygous for the Ragged (Ra) mutation in Sox18 exhibit chylous ascites and edema (Pennisi et al., Nat. Genet. 24:434-37. 2000), similar to the Chy mouse model of lymphedema (Lyon et al., Mouse News Lett. 71: 26. 1984). The mutation in Ra mice has been determined to be a frameshift mutation that causes truncation of the transactivating domain (Pennisi et al., Nat. Genet. 24:434-37. 2000). Sox18 null mice, however, demonstrate only a slight phenotypic change in hair follicle development and show no signs of edema or irregular vascular development (Downes and Koopman, Trends Cardio. Med. 11:318-24. 2001). This phenotype may be due to redundancy among the Group F Sox members, SOX7 and SOX17. These proteins may substitute for SOX18 function in its absence, but cannot overcome a Sox18 dominant negative mutant such as the Ra mutations. Hence, knocking out the entire Group F family may produce a lymphedema phenotype similar to the Ragged mice.

Mouse and human SOX18 are homologous proteins containing a DNA binding HMG-box of approximately 80 amino acids (97% homologous), a transactivating domain which in mouse is about 93 amino acids (90% homologous), and a C-terminal domain (92% homologous) (Downes and Koopman, supra). The human SOX18 HMG-box has been localized to nucleotides 395-598, corresponding to amino acids 84-151. The mouse HMG-box is encoded by nucleotides 320-532, corresponding to amino acids 78-148. The human transactivation domain has not been delineated to date, but one of skill in the art could readily obtain the human transactivating domain using the -homologous mouse sequence, which is found at amino acids 252-346 of mouse SOX18 (Hosking et al., Gene 262:239-47. 2001). Although the human SOX18 protein exhibits similarities to mouse SOX18 at the primary structural level, there is no known association of a human Sox18 mutant with a disease or condition, such as hereditary lymphedema.

Human Sox18 has been mapped to chromosome 20q.13.3 (Stanojcic et al., Biochem. Biophys. Acta. 1492:237-41. 2000). Elucidation of an inheritable mutation at or near this chromosomal location that correlates with hereditary lymphedema is useful in confirming the genetic basis of the disease, in the screening of patients affected by hereditary lymphedema, in the screening of patients for a pre-disposition to develop hereditary or other forms of lymphedema, and also as a basis for target treatment regimens directed to overcoming the inherited mutation.

To determine the linkage of Sox18 with lymphedema, families with inherited lymphedema are identified for the purpose of conducting linkage and positional candidate gene analyses. Family members are considered affected with hereditary lymphedema if they exhibit asymmetry or obvious swelling of one or both legs or if they have received a medical diagnosis of lymphedema or if there are personal or family reports of extremity swelling or asymmetry.

Biological samples are obtained from members of the families to conduct the genetic analyses. DNA is isolated from EDTA-anticoagulated whole blood by the method of Miller et al., (Nucleic Acids Res. 16:1215. 1998), and from cytobrush specimens using the Puregene DNA isolation kit (Gentra Systems, Minneapolis, Minn.). Analysis of the markers used in the genome scan are performed by methods recognized in the art. See Browman et al., Am. J. Hum. Genetic., 63:861-869 (1998); see also the NHLBI Mammalian Genotyping Service.

To explore the potential role of Sox18 in lymphedema, probands from the lymphedema families are screened for variation by direct sequencing of portions of the Sox18 gene. The sequencing strategy uses amplification primers generated based upon the Sox18 cDNA sequence (SEQ ID NO: 53) and information on the genomic organization (intron-exon data, identified domain motifs) of the related Sox genes. Variable positions (single nucleotide polymorphisms) and unique sequence primers are used to amplify sequences flanking each variable site located in the domains used for analysis.

The Sox18 genomic DNA from both the normal and lymphedema affected individuals is sequenced and a map of mutations detected in the Sox18 gene of lymphedema patients as compared to unaffected individuals is generated. Commonly detected mutations in lymphedema patients, such as a conservative or non-conservative nucleotide change, a deletion, or an insertion, indicates that a mutation in that particular nucleotide confers a pre-disposition to developing lymphedema. Analysis of the genomic DNA of the affected individuals will correlate mutations in the Sox18 genomic sequence and lymphedema.

To confirm the correlation of Sox18 mutations and the development of lymphedema, genetic linkage studies are performed, as set out in the method of identifying genetic polymorphisms described in U.S. patent application number US2003026759 and PCT/US99/06133, each of which is incorporated herein by reference.

Two-point linkage analysis is conducted using an autosomal dominant model predicting 80% penetrance in the heterozygous state, 99% penetrance in the homozygous state, and a 1% phenocopy rate. The frequency of the disease allele is set at 1/10,000. Microsatellite marker allele frequencies are calculated by counting founder alleles, with the addition of counts of non-transmitted alleles. Multipoint analysis is carried out using distances from the Location Database provided by the University of Southampton School of Medicine. Multipoint and 2-point analyses are facilitated using the VITESSE (v1.1) program. (O'Connell, and Weeks, Nature Genet., 11:402-408. 1995).

Analysis of the markers used in the genome scan are performed by methods recognized in the art. [See Browman et al., Am. J. Hum. Genetic., 63:861-869 (1998); see also the NHLBI Mammalian Genotyping Service and databases offered by the Center for Molecular Genetics (Marshfield, Wis.). One of skill in the art readily chooses genetic linkage markers identified in chromosome 20 (specifically 20q13.3), where Sox18 has been localized (Stanojcic et al., supra).

Linkage simulation is performed using SLINK (Weeks et al., Am. J. Hum. Genet. 47:A204. 1990) and linkage is analyzed using MSIM (Ott, J., Proc. Nat. Acad. Sci. USA, 86:4175-4178. 1989) to estimate the potential power of two point linkage analysis in the family being assessed. Marker genotypes are simulated for a marker with heterozygosity of 0.875 under a linked (θ=0) and unlinked (θ=0.5) model using the available individuals. The simulation is set such that the power to detect linkage is greater than 90% for a LOD score threshold of Z(θ) 2.0 and the false positive rate is less than 5%.

Mutations that correlate strongly with a heritable lymphedema are expected to be mutations in functional domains of the SOX18 protein, e.g., the HMG-Box domain or the transactivating domain. Exemplary mutations include missense mutations that cause non-conservative substitutions, nucleotide deletions or insertions that cause frameshifts in the Sox18 coding region, in-frame deletions or insertions such as those affecting a functional domain(s), or alterations of control regions affecting the level of Sox18 expression.

Upon identification of the Sox18 lymphedema-correlated mutations, Sox18 mutant expression vectors containing an isolated mutant Sox18 allele is expressed in, e.g., 293T or endothelial cells. The Sox18 mutant DNA can also be integrated into a plasmid useful in the mammalian two-hybrid system, such as pGAL4, to measure SOX18 interaction with its binding partners, such as MEF2C (Hosking et al., Biochem. Biophys. Res. Comm. 287: 493-500. 2001) or to screen for SOX18 binding partners. For example, pGAL4Sox18 vector links the Sox18 gene to the yeast Gal4 DNA binding domain and a transcriptional activator is linked to a SOX18 binding partner in a separate vector. Co-introduction of these vectors into a host cell will result in detectable reporter gene expression resulting from SOX18 interactions with the binding partner or candidate binding partner. The pCMV-BD and pCMV-AD vectors, which contain a GALA DNA binding domain and the NF-κB transcriptional domain, respectively, are useful in this assay (BD Biosciences Clontech) for constructing and expressing gene fusions, with SOX18 binding activity detected using the luciferase reporter system.

In such a di-hybrid assay, a Sox18 lymphedema-correlated mutant that contains a mutation affecting SOX18 binding via the transactivating domain will decrease the amount of luciferase reporter activity, indicating that the Sox18 lymphedema-correlated mutation may result in lymphedema through a defect in its ability to bind its binding partner through its transactivating domain.

A Sox18 allele is also assessed for a mutation in its HMG-box DNA binding domain through several techniques. DNA binding is assessed in a one-hybrid assay in which the DNA sequence bound by SOX18, e.g. 5′-(A/T)(A/T)CAA(A/T)G-3′ and permutations thereof, is placed in front of (i.e., upstream of or 5′ to) a promoter/reporter gene construct similar to the target plasmid in a two-hybrid assay. The reporter assay then detects binding between a SOX18 protein and its putative DNA binding sequence. DNA binding is also assessed using a gel shift assay performed by incubating a purified SOX18 protein with a ³²P end-labeled DNA fragment containing the SOX18 DNA-binding sequence. The reaction products are then analyzed on a non-denaturing polyacrylamide gel to measure the mobility of DNA-bound or free SOX18. The specificity of a SOX18 polypeptide for the putative binding site is established by competition experiments using DNA fragments or oligonucleotides containing a binding site for SOX18 or other unrelated DNA sequences.

Additionally, fluorescence-based assays for detection of DNA/protein binding are used. SOX18 DNA binding is detected by fluorescence measurement of single fluorophores which are bound to either the DNA or protein. In these assays, protein binding is determined by a change in fluorescence intensity or polarization when DNA-protein complexes form. Alternatively, two DNA fragments, each containing half of the protein binding site, are generated. The two double-stranded DNA fragments have complementary single-strand overhangs that comprise part of the protein binding site. One DNA fragment is labeled with a fluorescence donor while the other is labeled with an acceptor, with fluorescence detected only upon fluorescence resonance energy transfer (FRET). Upon protein binding, the overhangs of the two DNA fragments anneal and bring the fluorescence donor and acceptor into proximity, resulting in transfer of the fluorescence energy, which results in detectable fluorescence of the acceptor. See Heyduk, et al., Nat. Biotechnol. 20:171-6. 2002.

Correlation of a mutation in the human Sox18 genome with the risk of developing lymphedema provides another method for diagnosis and/or treatment of individuals affected by hereditary lymphedema. Elucidation of a Sox18 mutation associated with lymphedema allows for the determination of the SOX18 protein activity is disturbed by the mutation, e.g., DNA binding or protein binding, and provides direction for treatment of patients with lymphedema.

Additionally contemplated is the treatment of patients with Sox18-induced lymphedema with a lymphatic growth factor such as VEGF-C and/or VEGF-D to overcome impaired lymphatic vascular development. For example, treatment of VEGFR-3 defective animals with VEGF-C and/or VEGF-D overcomes the inability of VEGFR-3 to signal, thereby promoting lymphangiogenesis and ameliorating symptoms of lymphedema. Sox18-induced lymphedema patients are treated with a therapeutically effective amount of VEGF-C and/or VEGF-D. In an additional embodiment, VEGF-C and/or VEGF-D are administered to the above patients in conjunction with other therapies designed to relieve the symptoms of lymphedema.

Example 10

VEGF-C and VEGF-D knockout mice demonstrate aberrant vascular development which can be overcome by administration of exogenous VEGF-C and/or VEGF-D polypeptide. To determine if Sox18 transcriptional regulation can overcome this defect due to its potential interaction with, and transcriptional effect on, the VEGFR-3 promoter, VEGF-C or VEGF-D knockout mice are genetically crossed by interbreeding with mice overexpressing Sox18 from a cell-specific-promoter (e.g. K-14 keratin promoter) or a retroviral vector. The effects of Sox18 activity on lymphedema are assessed through measurement of lymphedema and vascular development, as described in Example 10.

Survival of the knockout mice and detection of lymphatic development in the VEGF-C and/or VEGF-D knockout/Sox18-overexpressing mice indicates that Sox18 induces VEGFR-3 signaling and plays a key role in lymphangiogenesis.

VEGF-C overexpressing mice (K-14-VEGF-C Tg) exhibit an extensive network of lymphatic vasculature, are prone to tumor metastasis, and demonstrate upregulated VEGFR-3 expression and symptoms of lymphedema (U.S. Pat. No. 6,361,946). To determine if Sox18 regulates VEGF-C signaling through VEGFR-3, K-14-VEGF-C Tg mice are crossed to animals which express a naturally mutated Sox18 (Ragged mutation) or a laboratory-designed mutant constructed using site-directed mutagenesis and standard knockout techniques known in the art to generate a mutation in either the DNA-binding or transactivating domain of the SOX protein, resulting in a K-14-VEGF-C Tg/Sox18^(−/−) mouse.

Decreased lymphangiogenesis, decreased incidence of tumor metastasis, and decreased levels of VEGFR-3 exhibited by the K-14-VEGF-C TgSox18^(−/−) double mutant animals as compared to the K-14-VEGF-C Tg single mutant animal indicates that the Sox18 molecule interferes with VEGF-C signaling through VEGFR-3 and that inhibition of the VEGFR-3 signaling in the Sox18 mutant downregulates the lymphangiogenic effects of activated VEGFR-3.

Alternatively, K-14-VEGF-C Tg mice are crossed to mice transgenic for a Sox18 allele that is overexpressed (see above) and the effects of Sox18 upregulation are measured. A decrease in lymphangiogenesis, decreased incidence of tumor metastasis, and decreased levels of VEGFR-3 exhibited by the K-14-VEGF-C Tg/Sox18 overexpressing double mutant animals as compared to the K-14-VEGF-C Tg single mutation indicates that Sox18 transcriptional regulation inhibits VEGFR-3 signaling and is likely a factor in negatively regulating lymphangiogenesis.

A result indicating that Sox18 is a negative regulator of lymphangiogenesis provides a method of treating disorders mediated by extensive lymphatic vasculature, such as lymphangiogenesis in tumor development or lymphangiosarcoma, by administration of a vector providing the SOX18 transcription factor in excess thereby preventing the induction of lymphangiogenic signals.

Example 11 Sox18 in Lymphatic Development

Lymphatic endothelial cells show a unique development pattern that is highly regulated by several LEC-specific genes such as VEGFR-3 and Prox-1. Sox18, as a DNA binding protein and transcription factor, is expected to be involved in the regulation of these LEC-specific genes, contributing to the elaboration of a LEC cellular fate. Several lines of evidence indicate that Sox18 may be involved in VEGFR-3 transcription regulation: SOX18 binds to the transcription factor MEF2C in mice, both Sox18-mutant and MEF2C-deficient mice exhibit lymphedema symptoms similar to VEGFR-3 mutant mice, and the VEGFR-3 promoter contains a MEF2C binding site (Iljin et al, FASEB J. 15:1028-36. 2001). These observations support a role for SOX18 in lymphatic development.

To analyze the ability of Sox18 to affect the transcription of LEC-specific growth factors, blood vascular endothelial cells are induced to develop into LECs by the addition of an AdProx-1 vector. Sox18 mRNA and protein levels are measured before and after the addition of the Prox-1 vector. Upregulation of Sox18 after the addition of the Prox-1 vector is expected to correlate with the development of lymphatic endothelial cells, indicating that Sox18 is a factor in. LEC differentiation. Alternatively, either the DNA binding or transactivation activity of Sox18 is disrupted via site-directed mutagenesis, thereby resulting in either a dominant negative or inactive SOX18 protein. The plasmid containing the Sox18-disrupted allele is co-transfected into BECs with the AdProx-1 vector to assess LEC development in the presence of a dysfunctional Sox18 gene. Detection of LEC-specific markers such as LYVE-1 and podoplanin are also used in these experiments to measure the ability of Sox18 to modulate lymphatic development. Additionally, mutant Sox18 is also co-transfected with vectors encoding LEC-specific proteins (e.g., VEGFR-3, Prox-1, LYVE-1) into 293T cells and the ability of the mutated Sox18 to regulate the activities of those genes is assessed. For example, signaling in VEGFR-3 co-transfected 293T cells stimulated with VEGF-C in the presence and absence of Sox18 is assessed using a phosphorylation assay.

Development of the lymphatic vasculature can also be evaluated in Sox18 mutant mice, including Ra mice, Sox18 null mice, and Sox18 mice transgenic for a mutation described herein that correlates with a pre-disposition to lymphedema. Transgenic Sox18 mice exhibiting a symptom of lymphedema are engineered to express a mutation in the mouse gene homologous to the human mutation or are engineered to express the human Sox18 gene containing a lymphedema-specific mutation. Development of the vasculature in these animals is analyzed, as set out in U.S. Pat. No. 6,361,946 (see also Kaipainen et al., Proc. Natl. Acad. Sci. (USA), 92:3566-70. 1995), using techniques known in the art, such as in situ hybridization, to detect VEGF-C and/or VEGFR-3 mRNA expression, antibody detection of VEGF-C and/or VEGFR-3 proteins in vivo, and Evan's blue dye detection to determine the extent of LEC development and to visualize effective lymph drainage in vivo.

An increase in VEGFR-3 signaling in a dominant negative Sox18 mutant transfectant indicates that Sox18 expression has a detrimental effect on VEGFR-3-mediated activity. The invention contemplates a therapy to overcome this type of mutation comprising administering to mammal, such as a human patient, a composition comprising a SOX18 inhibitor, such as a dominant negative gene or dominant negative Sox18 ligand which interferes with the ability of SOX18 to interfere with VEGFR-3 signaling. Alternatively, if Sox18 activation promotes VEGFR-3 activity this provides an indication that a therapy for lymphedema comprises a composition which promotes SOX18 transcriptional activity, such as cells given ex-vivo which overexpress Sox18.

Example 12 Sox18 Directed Therapy in Lymphedema

Another aspect of the invention is the use of Sox18 to produce cell-based therapeutic compositions, particularly LEC cell-based compositions. In one embodiment, the cells are autologous cells, i.e., cells of the organism (e.g., human patient) receiving treatment for a disease or disorder of the lymphatic system. The invention contemplates elevating the endogenous expression of Sox18, for example by the modification of expression control regions, e.g., promoters, through recombinant techniques such as homologous recombination. Alternatively, the cells are transformed or transfected with an isolated Sox18, e.g., a heterologous Sox18, for heterologous Sox18 expression, either in vivo or ex vivo.

For example, SOX18 interacts with transcription factor MEF2C, with the complex binding to the VEGFR-3 promoter, thereby inducing VEGFR-3 transcription and affecting VEGFR-3 protein expression and signaling levels. It is contemplated that insertion of a Sox18 gene driven by a retroviral or adenoviral vector into an LEC expressing VEGFR-3 will upregulate VEGFR-3-mediated signaling.

These Sox18-expressing cells are then used as a therapeutic composition in the treatment of patients with an LEC disease or disorder, such as hereditary lymphedema or trauma-induced lymphedema These cells are used to treat any disease or condition associated with a decrease in expression of VEGFR-3, such as lymphangioma, lymphangiomyeloma, lymphangiomatosis, lymphangiectasis, lymphosarcoma, and lymphangiosclerosis.

Additionally, a SOX18 polypeptide or polypeptide fragment is administered to a patient experiencing lymphedema to relieve the symptoms of lymphedema. It is contemplated that administration of either a full-length SOX18 polypeptide or a fragment of SOX18, which contains either the DNA binding domain or the transactivating domain, will bind to its cognate binding partner in vivo and promote VEGFR-3 signaling, or will initiate downstream events in the lymphangiogenic process, thus bypassing a defect in VEGFR-3 signaling or VEGF-C ligand binding involved in lymphedema.

In a related aspect, if SOX18 expression inhibits VEGFR-3 signaling via decreased transcription factor binding or DNA binding, it is expected that inhibition of SOX18 will result in a compensatory upregulation of VEGFR-3, ameliorating deleterious symptoms associated with VEGFR-3 under-expression. Administration of antisense therapy specific for the Sox 18 gene in instances where Sox 18 negatively regulates VEGFR-3 activity will inhibit SOX18 activity thereby allowing VEGFR-3-mediated signaling and lymphatic growth. Due to the potential functional redundancy of the Group F SOX proteins (SOX7/17/18), however, it may be necessary to inactivate all three proteins through a mechanism that inhibits the DNA binding activity of all Group F proteins. This is done, e.g., by targeting the DNA binding domain, which is highly homologous among all the proteins. It is contemplated that recombinant SOX7/17/18 proteins expressing a mutated DNA binding domain, when administered as a pharmaceutical composition (containing all three mutant peptides), will inhibit SOX18 downregulation of VEGFR-3 and induce or promote VEGFR-3 signaling activity. From the foregoing it will be appreciated that, although specific embodiments of the invention have been described herein for purposes of illustration, various modifications may be made without deviating from the spirit and scope of the invention.

All of the above U.S. patents, U.S. patent application publications, U.S. patent applications, foreign patents, foreign patent applications and non-patent publications referred to in this specification and/or listed in the [Application Data Sheet] are incorporated herein by reference, in their entirety. TABLE 3 Lymphatic EC (187 genes) Gene expression analysis Confirmed accession Affymetrix Detection¹ signal log by: signal log numbers ID BEC LEC ratio² s.d.³ NB IF ratio lung type-I cell membrane-associated AF030428 NM_006474 41870_at A P 7.4 0.925 + protein, podoplanin lung type-I cell membrane-associated AI660929 NM_006474 41871_at A P 6.1 0.150 + protein, podoplanin cellular retinol-binding protein M11433 NM_002899 38634_at A P 7.3 0.255 macrophage mannose receptor M93221 36908_at A P 7.1 0.682 (MRC1) transcription factor C-MAF AF055376 NM_005360 41504_s_at P P 5.1 0.522 transcription factor C-MAF AF055376 NM_005360 41505_r_at A P 3.9 0.588 selenoprotein P Z11793 NM_005410 34363_at A P 5.0 0.331 KIAA0466, immunoglobulin AB007935 NM_001542 38086_at A P 4.9 2.028 superfamily, member 3 type II membrane protein similar to AB015629 NM_014257 39270_at A P 4.9 0.846 HIV gp120-binding C-type lectin, CD209 antigen-like KIAA0626 AB014526 NM_021647 33241_at A P 4.7 0.212 KIAA0711 AB018254 NM_014867 36453_at A P 4.6 0.055 + integrin alpha 9 D25303 NM_002207 1508_at A P 4.3 0.712 + + integrin alpha 9 D25303 NM_002207 35948_at A P 3.6 1.086 + + relaxin H2 X00948 NM_005059 31732_at A P 4.1 0.432 KIAA0644 AB014544 NM_014817 34214_at A P 3.9 0.803 + Cdk-inhibitor p57KIP2 (KIP2) U22398 NM_000076 1787_at A P 3.8 2.020 + 3.3 Cdk-inhibitor p57KIP2 (KIP2) U22398 NM_000076 39545_at A P 3.0 0.150 + 1.4 transient receptor potential channel AJ006276 NM_004621 36365_at A P 3.8 0.988 TRPC6 cDNA DKFZp564O222 (from clone AL050002 38312_at A P 3.6 0.876 DKFZp564O222) subtilisin-like protein (PACE4), M80482 NM_002570 32001_s_at P P 3.6 0.334 paired basic amino acid cleaving system 4 regulator of G-protein signalling 16, U70426 NM_002928 41779_at A P 3.6 0.673 A28-RGS14p dihydropyrimidinase related protein- D78012 NM_001313 40272_at A P 3.5 1.192 1, collapsin response mediator protein 1 desmoplakin (DPI, DPII) AL031058 NM_004415 36133_at A P 3.5 0.426 + 1.0 pendrin, solute carrier family, AF030880 NM_000441 36376_at A P 3.3 1.156 member 4 reelin (RELN) U79716 NM_005045 37530_s_at P P 3.3 0.142 integrin, alpha 1 X68742 120_at P P 3.3 0.080 + integrin alpha 1 X68742 37484_at M P 2.4 0.345 + cholesterol 25-hydroxylase AF059214 NM_003956 32363_at A P 3.3 0.137 1.5 inhibin beta-B-subunit precursor M31682 NM_002193 38545_at P P 3.2 0.056 3.0 KIAA1233 AL109724 38856_at A P 3.1 1.540 pre-B cell stimulating factor L36033 NM_000609 33834_at A P 3.0 0.860 RT- homologue (SDF1b) PCR V-Erba Related Ear-3 Protein HG3510-HT3704 1147_at P P 2.9 0.398 1.7 antigen identified by monoclonal X05323 37716_at P P 2.9 0.283 + 1.0 antibody MRC OX-2 apolipoprotein D J02611 NM_001647 36681_at M P 2.9 0.150 + TIMP3, tissue inhibitor of matrix U14394 NM_000362 1035_g_at A P 2.8 0.528 + metalloproteinases TIMP3 U14394 NM_000362 1034_at P P 1.9 0.224 + aldehyde dehydrogenase 1 K03000 NM_000689 37015_at P P 2.8 0.275 prospero-related homeobox 1 (prox U44060 NM_002763 31918_at A P 2.8 0.299 + + (5, 6) 1) matrix Gla protein AI953789 NM_000900 36683_at A P 2.6 0.250 + neuronal pentraxin II (NPTX2) U29195 35663_at A P 2.6 1.267 2.9 histatin 2 (HIS2) M26665 NM_000200 41148_at A P 2.6 1.009 ADDL mRNA for adducin-like D67031 NM_016824 33102_at P P 2.6 0.277 + protein, adducin 3 (gamma) adducin 3 (gamma) U37122 NM_016824 33103_s_at M P 2.4 0.397 + MADS box transcription enhancer L08895 NM_002397 37710_at A P 2.5 0.540 + factor 2, polypeptide C (myocyte enhancer factor 2C) MADS box transcription enhancer NM_002397 37712_g_at A P 1.9 0.197 + factor 2, (myocyte enhancer factor 2C) MADS box transcription enhancer S57212 NM_002397 37711_at A P 1.4 0.442 + factor 2, polypeptide C (myocyte enhancer factor 2C) phosphoglucomutase 5 L40933 NM_021965 33694_at A P 2.5 0.431 cyclin E2 AF102778 NM_004702 35249_at A P 2.5 0.906 5.8 interleukin 7 (IL7) M29053 33966_at A P 2.4 0.191 interleukin 7 J04156 NM_000880 1159_at A P 1.9 0.921 cDNA DKFZp586L0120 (from clone AL050154 38351_at P P 2.4 0.135 DKFZp586L0120) peroxisome proliferative activated L40904 NM_005037 37104_at A P 2.4 0.502 receptor, gamma, PPARG fatty acid binding protein 4 AA128249 NM_001442 38430_at P P 2.4 0.132 protein kinase C zeta Z15108 NM_002744 362_at P P 2.4 0.008 46 kDa coxsackievirus and Y07593 NM_001338 37534_at P P 2.3 0.137 2.2 adenovirus receptor (CAR) protein PAC clone RP4-751H13 from 7q35-qter, AC004877 39837_s_at A P 2.3 0.714 zinc finger-like thymidine kinase 1, soluble M15205 NM_003258 910_at P P 2.3 0.205 2.1 thymidine kinase 1 K02581 NM_003258 41400_at M P 1.7 0.193 1.4 Pig7 (PIG7), LPS-induced TNF-alpha AF010312 NM_004862 37024_at A P 2.3 0.233 4.6 factor LPS-induced TNF-alpha factor AL120815 NM_004862 37025_at P P 1.3 0.327 3.8 lipase A, lysosomal acid, cholesterol X76488 NM_000235 38745_at P P 2.3 0.281 esterase ubiquitin specific protease 13 U75362 NM_003940 40701_at A P 2.2 0.334 (isopeptidase T-3) carcinoembryonic antigen-related cell X16354 NM_001712 988_at P P 2.2 0.048 adhesion molecule 1 (biliary glycoprotein) CEACAM1 cDNA DKFZp586D0918 (from clone AL049370 41856_at P P 2.1 0.385 DKFZp586D0918) KIAA0598, B cell RAG associated AB011170 NM_014863 35350_at P P 2.1 0.154 protein RAMP2 (receptor (calcitonin) AJ001015 NM_005854 38177_at P P 2.1 0.361 activity modifying protein 2) cholesteryl ester transfer protein M30185 NM_000078 40741_at A P 2.1 0.191 precursor epithelial membrane protein 2 U52100 NM_001424 39631_at P P 2.0 0.141 1.0 MHC class II lymphocyte antigen M83664 NM_002121 38095_i_at A P 2.0 1.368 (HLA-DP) beta chain MHC class II lymphocyte antigen M83664 NM_002121 38096_f_at A P 1.2 0.034 (HLA-DP) beta chain beta-arrestin 2 AF106941 NM_004313 33283_at A P 2.0 0.273 mitotic checkpoint kinase Bub1 AF053305 NM_004336 41081_at A p 2.0 0.195 (BUB1) KIAA0229, similar to human ankyrin D86982 40971_at P P 2.0 0.195 1.6 1(S08275) Sprouty 1 homolog (antagonist of AF041037 38767_at P P 2.0 0.209 FGF signaling) guanine nucleotide exchange factor NM_012294 38062_at P P 2.0 0.497 2.1 for Rap1; M-Ras-regulated GEF, KIAA0277 translin X78627 NM_004622 36177_at A P 2.0 0.140 erythrocyte membrane protein band U28389 NM_0019178 37192_at P P 2.0 0.265 1.9 4.9 (dematin) KIAA0846 protein AB020653 NM_015376 34748_at A P 2.0 0.457 glia maturation factor, gamma W07033 NM_004877 35261_at P P 1.9 0.083 1.0 insulin-like growth factor binding X16302 NM_000597 40422_at A P 1.9 1.157 protein 2 (IGFBP-2) smooth muscle myosin heavy chain S67247 32838_at A P 1.9 0.179 isoform Smemb TTG-2 (cysteine rich protein with X61118 NM_005574 32184_at P P 1.9 0.221 1.0 LIM motif), LIM domain only 2 (rhombotin-like 1) cyclin B2 AL080146 NM_004701 32263_at A P 1.9 0.276 KIAA0353 AB002351 39544_at P P 1.9 0.158 1.8 KIAA0559, piccolo (presynaptic AB011131 37780_at A P 1.9 0.330 cytomatrix protein) G protein-coupled receptor, family C, AC00413 NM_016235 40240_at P P 1.9 0.047 2.1 group 5, member B G protein-coupled receptor, family C, AI801872 NM_016235 40239_g_at P P 1.4 0.303 group 5, member B CREM (cyclic AMP-responsive S68134 NM_001881 32066_g_at P P 1.9 0.098 1.7 element modulator beta isoform) CREM (cyclic AMP-responsive S68134 NM_001881 32065_at P P 1.8 0.241 2.0 element modulator beta isoform) CREM (cyclic AMP-responsive S68271 NM_001881 32067_at P P 1.5 0.182 2.0 element modulator beta isoform) hypothetical protein FLJ13110 AL080222 NM_022912 36096_at A P 1.9 0.387 inositol(myo)-1(or 4)- AF014398 NM_014214 36496_at A P 1.8 0.590 3.2 monophosphatase 2 KIAA0937 protein AB023154 35369_at P P 1.8 0.185 mitotic spindle coiled-coil related AF063308 NM_006461 32120_at A P 1.8 0.257 protein cysteine and glycine-rich protein 2 U57646 NM_001321 41401_at A P 1.8 0.431 4.3 (CSRP2) topoisomerase (DNA) II alpha AI375913 NM_001067 40145_at P P 1.8 0.239 1.0 (170 kD) DNA topoisomerase II J04088 NM_001067 1592_at P P 1.2 0.162 protein phosphatase inhibitor 2 U68111 33180_at P P 1.8 0.319 (PPP1R2) KIAA0186 D80008 NM_021067 39677_at A P 1.8 0.269 1.4 dual-specificity tyrosine-(Y)- Y12735 NM_003582 39931_at P P 1.8 0.146 phosphorylation regulated kinase 3 (Dyrk3) kinesin-like spindle protein HKSP U37426 NM_004523 40726_at M P 1.8 0.439 (HKSP) huntingtin-associated protein U94190 NM_003947 40655_at P P 1.8 0.529 1.4 interacting protein (duo) diubiquitin AL031983 NM_006398 39959_at A P 1.8 0.841 bikunin, serine protease inhibitor, U78095 NM_021102 34348_at A P 1.8 0.398 Kunitz type, 2 cytochrome P-450-1 (TCDD- K03191 NM_000499 36767_at A P 1.7 0.165 2.0 inducible) cytochrome P(1)-450 X02612 NM_000499 1025_g_at P P 1.1 0.125 1.7 KIAA0513 NM_014732 38735_at A P 1.7 0.297 protein phosphatase inhibitor 2 U68111 812_at P P 1.7 0.185 (PPP1R2) RAMP3 (receptor (calcitonin) AJ001016 NM_005856 35152_at P P 1.7 0.228 activity modifying protein 3) B-myb X13293 NM_002466 1854_at M P 1.7 0.455 2.3 KIAA0952 AB023169 NM_014962 37755_at P P 1.7 0.254 1.0 interferon stimulated gene (20 kD), U88964 NM_002201 33304_at A P 1.7 0.178 HEM45 GS3955 D87119 NM_021643 717_at P P 1.7 0.107 1.6 GS3955 D87119 NM_021643 40113_at P P 1.3 0.098 1.3 GRB2-related adaptor protein (Grap) U52518 NM_006613 805_at A P 1.7 0.147 KIAA1071 protein AB028994 38286_at A P 1.7 0.625 RNA-binding protein gene with D84111 NM_006867 34162_at P P 1.7 0.347 multiple splicing, RBP-MS/type 5 RNA-binding protein gene with D84111 NM_006867 34163_g_at P P 1.6 0.147 multiple splicing, RBP-MS/type 5 RBP-MS/type 4, RNA-binding protein D84110 NM_006867 1276_g_at P P 1.5 0.263 gene with multiple splicing RBP-MS/type 4, RNA-binding protein D84110 NM_006867 38049_g_at P P 1.3 0.268 gene with multiple splicing RBP-MS/type 3, RNA-binding protein D84109 NM_006867 38047_at P P 1.2 0.225 gene with multiple splicing alpha-actinin-2-associated LIM AF002282 NM_014476 39690_at A P 1.7 0.728 1.5 protein semaphorin-III (Hsema-I), L26081 NM_006080 33461_at A P 1.6 0.445 semaphorin 3A IQ motif containing GTPase U51903 NM_006633 1647_at M P 1.6 0.395 activating protein 2 Arrestin, Beta 2 HG2059-HT2114 957_at P P 1.6 0.342 retinoblastoma-associated protein AF017790 NM_006101 40041_at P P 1.6 0.153 2.0 HEC LIM domain binding protein (LDB1) AF052389 NM_001290 36065_at P P 1.6 0.153 1.9 dual specificity phosphatase 5 U15932 NM_004419 529_at P P 1.6 0.207 Homo sapiens cDNA 3′, mRNA AI557322 39611_at P P 1.6 0.081 sequence monoamine oxidase A (MAOA) M68840 NM_000240 41772_at P P 1.6 0.148 monoamine oxidase A AA420624 NM_000240 41771_g_at P P 1.4 0.230 NECDIN related protein U35139 NM_002487 36073_at P P 1.6 0.245 regulatory solute carrier protein, X82877 NM_006511 31695_g_at A P 1.6 0.916 family 1, member 1 TTK protein kinase M86699 NM_003318 572_at P P 1.6 0.196 fms-related tyrosine kinase 4, X69878 NM_002020 403_s_at A P 1.5 0.403 + + 1.1 VEGFR-3 TSC403, similar to lysosome- AB013924 NM_014398 37168_at P P 1.5 0.164 associated membrane glycoprotein HMG-2 X62534 38065_at P P 1.5 0.105 1.1 Homo sapiens clone 24416 mRNA AF052159 35342_at P P 1.5 0.253 sequence calcitonin receptor-like L76380 NM_005795 34995_at P P 1.5 0.509 1.4 KIAA0582 protein AI761647 NM_015147 40191_s_at M P 1.5 0.558 1.4 cDNA DKFZp434B102 (from clone AL080192 38630_at A P 1.5 0.719 DKFZp434B102) cDNA DKFZp586G1922 (from clone AL080110 39600_at P P 1.5 0.160 DKFZp586G1922) Acyl-CoA synthetase 3 D89053 NM_004457 33880_at P P 1.5 0.264 fatty-acid-Coenzyme A ligase, long- AA977580 NM_004457 33881_at P P 1.0 0.120 1.7 chain 3 STAT induced STAT inhibitor-2 AF037989 38994_at A P 1.5 0.391 Homeotic Protein Hox5.4 HG3502-HT3696 696_at P P 1.5 0.181 hypothetical protein FLJ13910, AL050139 NM_022780 36580_at P P 1.5 0.228 cDNA DKFZp586M141 (from clone DKFZp586M141) cDNA DKFZp586N012 (from clone AL049471 41690_at P P 1.4 0.320 DKFZp586N012) UbcH10, ubiquitin carrier protein E2-C U73379 NM_007019 1651_at P P 1.4 0.022 1.1 cyclin-dependent kinase inhibitor 3, L25876 NM_005192 1599_at P P 1.4 0.431 protein tyrosine phosphatase (CIP2) glycogen phosphorylase (PYGL) AF046798 37215_at P P 1.4 0.423 1.5 Angiopoietin-2 AF004327 NM_001147 1951_at P P 1.4 0.175 + 1.2 Angiopoietin-2 AF004327 NM_001147 37461_at P P 1.2 0.134 + forkhead box M1 U74612 NM_021953 34715_at M P 1.4 0.367 1.4 potentially prenylated protein AF041434 NM_007079 36008_at A P 1.4 0.094 2.3 tyrosine phosphatase hPRL-3 RAB31, Low Mr GTP-binding U59877 NM_006868 33371_s_at P P 1.4 0.299 protein of the Rab subfamily RAB31, member RAS oncogene AI189226 NM_006868 33372_at P P 1.2 0.444 family myosin VIIA U39226 NM_000260 33197_at P P 1.4 0.038 1.2 Grb2-associated binder-1, docking U43885 NM_002039 1249_at A P 1.4 0.073 protein related to IRS-1 lamin B1 L37747 37985_at P P 1.4 0.643 minichromosome maintenance D84557 NM_005915 40117_at P P 1.4 0.170 1.8 deficient (mis5, S. pombe) 6 HsMcm6 cyclin B1 M25753 1945_at P P 1.4 0.398 cyclin B1 M25753 34736_at P P 1.3 0.160 RTP, N-myc downstream regulated D87953 NM_006096 36933_at P P 1.4 0.131 alpha2,3-sialyltransferase AB022918 NM_006100 39298_at P P 1.4 0.150 ADP-ribosylation factor-like protein 4 U73960 NM_005738 33796_at P P 1.4 0.281 centromere protein F (350/400 kD, U30872 NM_016343 37302_at A P 1.4 0.245 mitosin) paternally expressed 10, KIAA1051 AB028974 NM_015068 39696_at P P 1.4 0.300 4.2 tubulin, alpha 1 (testis specific) X06956 36591_at M P 1.4 0.300 1.8 KIAA0101 D14657 NM_014736 38116_at P P 1.4 0.409 KIAA0128, septin 2 D50918 38826_at P P 1.4 0.381 1.8 protein phosphatase 2, regulatory Z69030 NM_002719 40785_g_at P P 1.4 0.453 subunit B (B56), gamma deoxycytidine kinase M60527 NM_000788 886_at A P 1.3 0.455 integrin beta 3 binding protein U37139 NM_014288 38501_s_at P P 1.3 0.171 (beta3-endonexin) TAL1 (SCL) interrupting locus M74558 NM_003035 32767_at M P 1.3 0.150 KIAA0666 AB014566 33753_at P P 1.3 0.356 cAMP-specific phosphodiesterase AF056490 37676_at P P 1.3 0.222 8A, PDE8A1 mitotic checkpoint kinase Mad3L AF053306 NM_001211 35699_at P P 1.3 0.216 1.6 (MAD3L), BUB1B ribosomal S6 kinase X85106 NM_021135 32892_at P P 1.3 0.145 HPTP epsilon (protein tyrosine X54134 NM_006504 32916_at P P 1.3 0.100 1.0 phosphatase epsilon) Lyn tyrosine kinase, v-yes-1 M79321 NM_002350 2024_s_at P P 1.3 0.054 + Yamaguchi sarcoma viral related oncogene homolog lyn tyrosine kinase, v-yes-1 M16038 NM_002350 1402_at P P 1.3 0.382 + Yamaguchi sarcoma viral related oncogene homolog lyn tyrosine kinase M16038 NM_002350 32616_at P P 1.2 0.066 + brachyury variant A (TBX1), T-box 1 AF012130 NM_005992 32285_g_at P P 1.3 0.352 transcription factor mki67a mRNA (long type) for X65550 NM_002417 418_at A P 1.3 0.357 1.5 antigen of monoclonal antibody Ki- 67 protein tyrosine phosphatase receptor U81561 NM_002847 36160_s_at P P 1.3 0.193 pi (PTPRP) cbl-b U26710 NM_004351 514_at A P 1.3 0.482 Cyclin A2 X51688 NM_001237 1943_at P P 1.3 0.277 nucleoside phosphorylase X00737 NM_000270 430_at P P 1.3 0.272 TNF-related apoptosis inducing U37518 NM_003810 1715_at P P 1.3 0.316 ligand TRAIL phosphodiesterase 4B, cAMP- L20971 NM_002600 33705_at P P 1.3 0.275 specific nidogen (enactin) M30269 NM_002508 35366_at P P 1.3 0.050 HYA22 protein D88153 NM_005808 40196_at P P 1.3 0.150 1.3 phosphatidic acid phosphatase type AF014402 NM_003711 34797_at P P 1.3 0.191 2A KIAA0512, ALEX2 AB011084 NM_014782 36057_at P P 1.2 0.268 thromboxane A2 receptor D38081 NM_001060 336_at M P 1.2 0.385 2.4 trefoil factor 3 (intestinal) AI985964 NM_003226 37897_s_at P P 1.2 0.183 G-2 and S-phase expressed 1 AL031588 NM_016426 41660_at A P 1.2 0.424 3.1 ADP-ribosyltransferase (NAD+; poly AJ236876 NM_005484 34756_g_at M P 1.2 0.362 1.1 (ADP-ribose) polymerase)-like 2 serine/threonine kinase 12 AF015254 NM_004217 33266_at P P 1.2 0.126 Tubulin, Alpha 1, Isoform 44 HG2259-HT2348 330_s_at P P 1.2 0.096 1.1 lamin B receptor L25931 NM_002296 288_s_at P P 1.2 0.141 KIAA0429 AB007889 NM_014751 37363_at P P 1.2 0.150 2.5 transcription factor 4 M74719 NM_003199 36605_at P P 1.2 0.050 1.1 syndecan 3 (N-syndecan), KIAA0468 AB007937 NM_014654 32092_at P P 1.2 0.206 1.0 RECK protein precursor AA099265 NM_021111 35236_g_at P P 1.2 0.173 Putative prostate cancer tumor U42349 NM_006765 36852_at P P 1.1 0.082 1.1 suppressor protein phosphatase 1, regulatory AB020630 41577_at P P 1.1 0.082 (inhibitor) subunit PDZ and LIM domain 1 (elfin) U90878 NM_020992 36937_s_at P P 1.1 0.096 hypothetical protein from clone 643 AF091087 NM_020467 34176_at P P 1.1 0.096 1.1 p53-regulated DDA3 AA926959 37347_at P P 1.1 0.058 KIAA0062 D31887 38797_at P P 1.1 0.058 medium-chain acyl-CoA M91432 37532_at P P 1.1 0.308 dehydrogenase gap junction protein, alpha 1, 43 kD M65188 NM_000165 2018_at P P 1.1 0.329 (connexin 43) MyoD family inhibitor U78313 NM_005586 38156_at P P 1.1 0.381 endo/exonuclease Mre11 (MRE11A) AF073362 NM_005591 32869_at P P 1.1 0.642 nuclear receptor subfamily 2, group X16155 NM_005654 39294_at A P 1.0 0.446 F, member 1 ¹A measurement indicating whether the transcript was detected (present, P), not detected (absent, A) or marginally detected (marginal, M; also if P in one experiment but A in another) ²The change in expression level for a transcript between two independently harvested BECs and LECs (=total of 4 comparisons). The change is expressed as the log2 ratio. ³Standard deviation of the change in the expression level (in 4 comparisons) NB = Northern blot, IF = immunofluorescence

TABLE 4 Blood Vascular EC (222 genes) Gene expression analysis Confirmed accession Affymetrix Detection¹ signal log by: signal log numbers ID BEC LEC ratio² s.d.³ NB IF ratio p27 mRNA, interferon alpha- X67325 NM_005532 425_at P A 8.3 0.620 1.5 inducible protein 27 ribonuclease A (RNase A), D26129 NM_002933 37402_at P A 7.2 0.208 2.7 pancreatic hematopoietic neural membrane U87947 NM_001425 39182_at P A 5.9 0.381 1.6 protein (HNMP-1) N-cadherin M34064 NM_001792 2054_g_at P A 5.7 1.345 + N-cadherin M34064 NM_001792 2053_at P P 3.7 0.514 + interleukin 8 (IL8) M28130 NM_000584 1369_s_at P A 5.3 1.477 + interleukin 8, beta- M17017 NM_000584 35372_r_at P P 2.8 0.406 + 1.1 thromboglobulin-like protein precursor tyrosine kinase receptor (axl) M76125 NM_001699 38433_at P A 5.1 1.112 + 1.0 Tyrosine Kinase, Receptor Axl, Alt. HG162- 1278_at P A 4.7 0.937 + 1.1 Splice 2 HT3165 cell surface glycoprotein CD44 L05424 1126_s_at P A 4.9 1.527 1.9 (CD44) cell adhesion molecule (CD44) M59040 NM_000610 2036_s_at P A 1.9 0.402 2.6 hyaluronate receptor (CD44) L05424 40493_at P P 1.9 0.136 2.0 vascular endothelial growth factor U43142 NM_005429 159_at P A 4.6 0.850 + related protein VRP, VEGF-C Vascular endothelial growth factor C X94216 NM_005429 1934_s_at P A 4.4 1.342 + collagen type XIII, alpha 1 M33653 NM_005203 38952_s_at P A 4.5 0.213 2.7 (=COL4A2) collagen type XIII, alpha-1 M59217 NM_005203 38951_at P A 3.6 1.683 1.1 collagen alpha-2 type I K01079 32306_g_at P A 4.5 2.161 collagen alpha-2 type I K01079 32305_at P A 2.8 1.464 collagen, type I, alpha 2 V00503 NM_000089 32307_s_at P A 2.4 1.394 proteoglycan 1 X17042 NM_002727 32227_at P P 4.3 0.385 1.0 phospholipase A2, group IVA, M72393 35938_at P A 4.3 2.398 1.9 calcium-dependent phospholipid- binding protein (PLA2) carbohydrate (keratan sulfate Gal-6) AB003791 NM_003654 41395_at P P 4.2 0.232 sulfotransferase tropomyosin 2 (beta), fibroblast M12125 NM_003289 32314_g_at P A 4.2 1.845 tropomyosin chondroitin sulfate proteoglycan 2 X15998 NM_004385 38111_at P A 4.1 1.746 1.5 (versican) chondroitin sulfate proteoglycan 2 X15998 NM_004385 38112_g_at P A 2.0 1.219 (versican) latent transforming growth factor- Z37976 NM_000428 37906_at P P 4.1 0.381 1.1 beta binding protein (LTBP-2) interleukin 6 (interferon, beta 2) X04430 NM_000600 38299_at P A 4.0 0.776 2.0 bone morphogenetic protein-4 U43842 NM_001202 40333_at P A 4.0 0.883 (hBMP-4) bone morphogenetic protein 2B, M22490 NM_001202 1114_at P A 2.6 1.146 BMP-4 sarcolectin, keratin 7 AJ238246 NM_005556 41294_at P P 3.9 0.631 neuronal cell adhesion molecule, AB002341 NM_005010 37286_at P A 3.9 1.642 1.8 KIAA0343 neuronal cell adhesion molecule, U55258 NM_005010 37288_g_at P A 1.5 0.309 hBRAVO/Nr-CAM precursor matrix metalloproteinase 1 M13509 NM_002421 38428_at P P 3.9 0.521 + (interstitial collagenase), skin collagenase stem cell factor, KIT ligand M59964 NM_000899 597_at P A 3.9 0.554 + uPA X02419 NM_002658 37310_at P A 3.8 0.282 3.0 plasminogen activator inhibitor-1 J03764 NM_000602 672_at P P 3.7 0.161 1.6 plasminogen activator inhibitor 1 M14083 NM_000602 38125_at P P 2.9 0.118 1.9 selectin P, CD62, granule M25322 NM_003005 40366_at P P 3.6 1.869 1.2 membrane protein-140 (GMP-140) precursor latrophilin-2 AJ131581 NM_012302 34174_s_at P A 3.6 0.098 1.1 actin, alpha 2 X13839 NM_001613 32755_at P P 3.6 1.067 fibroblast activation protein, alpha U09278 NM_004460 39945_at P A 3.6 0.789 1.2 regulator of G-protein signalling 20 AF060877 NM_003702 41086_at P A 3.5 0.615 IGF-II mRNA-binding protein 3 U97188 NM_006547 37558_at P P 3.5 0.528 2.1 retina cDNA randomly primed W28438 36497_at P A 3.5 0.414 sublibrary, EST brain acid-soluble protein 1, AF039656 NM_006317 32607_at P A 3.4 0.104 1.6 neuronal tissue-enriched acidic protein (NAP-22) profilin 2 AL096719 NM_002628 38839_at P P 3.4 0.111 1.6 profilin 2 L10678 NM_002628 38840_s_at P P 3.1 0.076 1.6 Na,K-ATPase beta-1 subunit U16799 NM_001677 37669_s_at P A 3.4 0.249 Claudin-7 AJ011497 NM_001307 38482_at P A 3.4 0.798 normal gingiva U51712 39698_at P A 3.4 0.391 1.1 a disintegrin and metalloproteinase AB009672 NM_003812 40350_at P A 3.4 0.600 domain 23 COL8A1 mRNA for alpha 1(VIII) X57527 NM_001850 37459_at P A 3.3 0.819 + 1.7 collagen signal transducer and activator of AF067575 41222_at P P 3.3 0.338 + + 1.8 transcription 6 (STAT6) transcription factor IL-4 Stat, U16031 NM_003153 845_at P A 2.1 0.493 + + 1.6 STAT6 lipocortin-III, annexin A3 M20560 NM_005139 31792_at P P 3.3 0.265 1.1 intercellular adhesion molecule 1 M24283 NM_000201 32640_at P A 3.2 0.184 + (CD54), major group rhinovirus receptor precusor solute carrier family 1 U08989 NM_004170 38268_at P A 3.2 0.687 1.3 (neuronal/epithelial high affinity glutamate transporter, system Xag) solute carrier family 1 AI928365 NM_004170 38267_at P A 2.6 0.524 1.2 (neuronal/epithelial high affinity glutamate transporter, system Xag) p53 inducible protein L47738 37579_at P A 3.2 0.249 1.0 dihydropyrimidine dehydrogenase, U20938 NM_000110 38220_at P A 3.2 0.306 DPYD natural killer cell transcript 4 AA631972 NM_004221 39119_s_at P P 3.1 0.082 1.6 PFTAIRE protein kinase 1, AB020641 NM_012395 36502_at P A 3.1 0.841 KIAA0834 RGP4, regulator of G-protein U27768 NM_005613 34272_at P A 3.0 0.396 1.5 signalling 4 regulator of G-protein signalling 4 AI267373 NM_005613 34273_at P A 2.6 0.473 1.5 Oncogene Aml1-Evi-1, Fusion HG4058- 1882_g_at P M 2.9 0.590 1.5 Activated HT4328 Oncogene Aml1-Evi-1, Fusion HG4058- 1881_at P A 2.0 0.374 Activated HT4328 adenylyl cyclase-associated protein 2 N90755 NM_006366 33405_at P A 2.8 0.596 1.5 clusterin (complement lysis M25915 NM_001831 36780_at P P 2.8 0.161 inhibitor, SP-40, 40, sulfated glycoprotein 2, apolipoprotein J) ADP ribosylation factor-like 7 AB016811 NM_005737 39829_at P A 2.7 0.531 H factor (complement)-like 1 M65292 NM_002113 32249_at P A 2.7 0.589 RNA helicase-related protein, H68340 NM_007372 41446_f_at P P 2.7 0.296 metallothionein-If stimulated trans-acting factor X82200 NM_006074 36825_at P A 2.7 0.730 6.2 (50 kDa) Staf50 cyclooxygenase-2 (hCox-2) U04636 NM_000963 1069_at P A 2.6 1.281 GRO1 oncogene, melanoma growth X54489 NM_001511 408_at P A 2.6 0.369 stimulatory activity (MGSA) NRGN, neurogranin X99076 NM_006176 33925_at M A 2.6 1.237 homologue of mouse dkk-1 AB020315 35977_at P A 2.5 0.398 gastrointestinal tumor-associated J04152 NM_002353 291_s_at P P 2.5 0.139 antigen GA733-1, tumor-associated calcium signal transducer 2 laminin Z15008 NM_005562 35280_at P A 2.5 0.824 transgelin, 22 kDa smooth muscle M95787 NM_003186 36931_at P A 2.5 0.980 protein (SM22) JE gene encoding a monocyte M28225 34375_at P P 2.4 0.186 3.6 secretory protein zinc finger protein 238, RP58 AJ223321 NM_006352 35824_at P A 2.4 0.498 3.2 cathepsin C X87212 NM_001814 133_at P P 2.4 0.244 tissue-type plasminogen activator M15518 NM_000930 33452_at P A 2.4 0.479 (t-PA) sushi-repeat protein AF060567 NM_014467 37805_at P A 2.4 0.670 annexin A6 D00510 NM_001155 39082_at P A 2.4 0.181 1.2 EphrinB1 U09303 NM_004429 39721_at P A 2.4 0.946 EphrinB1 U09303 NM_004429 188_at P A 1.2 0.489 TFEC isoform (transcription factor D43945 NM_012252 34470_at P A 2.4 0.028 3.1 EC) small inducible cytokine A2, M26683 NM_002982 875_g_at P P 2.3 0.283 3.5 (monocyte chemotactic protein1) small inducible cytokine A2 M26683 NM_002982 874_at P A 1.2 0.385 (monocyte chemotactic protein 1) endothelial cell protein C/APC L35545 NM_006404 647_at P P 2.3 0.259 2.2 receptor (EPCR) transglutaminase 2 (TGase) M55153 NM_004613 231_at P M 2.3 0.413 transglutaminase (TGase) M55153 NM_004613 38404_at P P 1.6 0.093 human metallothionein-If M10943 31622_f_at P M 2.3 0.230 transforming growth factor beta- M77349 NM_000358 1385_at P A 2.3 0.951 induced (BIGH3) ENO2 gene for neuron specific X51956 40193_at P A 2.3 0.121 1.6 (gamma) enolase FAT tumor suppressor (Drosophila) X87241 NM_005245 40454_at P A 2.3 1.204 homolog malignant cell expression-enhanced S82470 NM_024298 181_g_at P P 2.2 0.469 gene/tumor progression-enhanced gene malignant cell expression-enhanced S82470 NM_024298 180_at P A 1.7 0.420 gene/tumor progression-enhanced gene cDNA DKFZp566G0746 (from AL050078 39324_at P A 2.2 1.281 clone DKFZp566G0746) lysyl oxidase-like 2 U89942 NM_002318 33127_at P P 2.2 0.274 ras-related C3 botulinum toxin M64595 NM_002872 32737_at P P 2.2 0.143 3.5 substrate 2 (rho family, small GTP binding protein Rac2) endothelial leukocyte adhesion M24736 NM_000450 265_s_at P A 2.2 0.448 molecule 1 (ELAM-1), selectin E laminin, alpha 5, KIAA0533 AB011105 41610_at P P 2.2 0.146 placenta growth factor (P1GF) X54936 NM_002632 793_at P P 2.2 0.301 + 1.0 ALL1-fused gene from U16954 NM_006818 36941_at P P 2.2 0.592 chromosome 1q, AF1q stromelysin-2, MMP-10 X07820 NM_002425 1006_at P P 2.1 0.159 1.0 metallothionein-I-A K01383 31623_f_at P P 2.1 0.238 collagen VI alpha-1 X15880 38722_at P A 2.1 0.898 mad protein homolog (hMAD-3) U68019 NM_005902 1433_g_at P A 2.1 0.269 1.1 mad protein homolog (hMAD-3) U68019 NM_005902 38944_at P A 1.8 0.367 1.4 mad protein homolog (hMAD-3) U68019 NM_005902 1454_at P A 2.0 0.304 integral membrane protein 2A AL021786 40775_at P P 2.1 0.570 interleukin 1 receptor-like 1 D12763 NM_003856 40322_at P A 2.1 0.718 high-mobility group (nonhistone X92518 35200_at P A 2.0 0.177 chromosomal) protein isoform I-C (HMGI-C) epidermal growth factor receptor U12535 NM_004447 1467_at P A 2.0 0.710 1.0 kinase substrate (Eps8) lactate dehydrogenase B X13794 NM_002300 33819_at P P 2.0 0.029 1.6 mRNA for unknown product D29810 40227_at P A 2.0 1.170 hypothetical protein AL033377 36014_at P A 2.0 0.137 1.1 DKFZp564D0462 lysyl hydroxylase isoform 2 U84573 NM_000935 34795_at P P 2.0 0.157 (PLOD2) follistatin-like 3, follistatin-related U76702 NM_005860 33900_at P A 2.0 0.075 2.6 protein (FLRG) Homo sapiens clone 24674 mRNA AF070578 36758_at P A 2.0 0.612 1.8 sequence L-iditol-2 dehydrogenase L29254 38763_at P A 1.9 0.140 neuronal pentraxin 1 U61849 NM_002522 37921_at P A 1.9 0.744 2.5 hypothetical protein from clones U90908 NM_021226 34010_at P A 1.9 0.870 23549 and 23762 UDP-N-acetylglucosamine AB011004 NM_003115 41242_at P P 1.9 0.342 pyrophosphorylase zinc finger protein 185 (LIM Y09538 NM_007150 32139_at P A 1.8 0.062 1.6 domain) four and a half LIM domains 2, U29332 NM_001450 38422_s_at P P 1.8 0.229 heart protein (FHL-2) mitogen-activated protein kinase- U09578 NM_004635 1637_at P A 1.8 0.454 1.4 activated protein kinase 3, MAPKAP kinase (3pK) metallothionein 1E (functional) R92331 36130_f_at P P 1.8 0.131 TU3A protein AF035283 NM_007177 38044_at P A 1.8 0.298 1.8 metallothionein 1H R93527 NM_005951 39594_f_at P P 1.8 0.415 guanylate binding protein isoform II M55543 NM_004120 32700_at P P 1.8 0.304 1.1 (GBP-2) soluble vascular endothelial cell U01134 NM_002019 1964_g_at P M 1.8 0.384 + growth factor receptor 1 (sVEGFR- 1) R-Ras M14949 38338_at P P 1.8 0.119 R-ras M14949 1879_at P P 1.2 0.330 1.5 creatine transporter (SLC6A8), U36341 NM_005629 40926_at P A 1.8 0.305 solute carrier family 6, member 8 target of myb1 (chicken) homolog, Z82244 NM_005488 33802_at P P 1.8 0.149 Heme Oxygenase 1 (HO-1) procollagen-lysine, 2-oxoglutarate L06419 NM_000302 36184_at P P 1.8 0.310 5-dioxygenase, lysyl hydroxylase (PLOD) KIAA0836 AB020643 33296_at P P 1.8 0.203 1.8 cDNA DKFZp434C171 (from clone AL080169 34183_at P A 1.8 0.606 1.2 DKFZp434C171) IL-4-R mRNA for the interleukin 4 X52425 NM_000418 404_at P P 1.7 0.244 receptor chemokine (C—C motif) receptor- AF014958 NM_003965 1445_at P A 1.7 0.386 1.8 like 2 (CCRL2), chemokine receptor X (CKRX) phospholipase C, beta 3 Z16411 NM_000932 364_s_at P A 1.7 0.098 (phosphatidylinositol-specific) LIM domain protein X93510 NM_003687 32610_at P P 1.7 0.067 1.9 protein kinase (cAMP-dependent, M34181 NM_002731 36215_at P A 1.7 0.315 1.0 catalytic) inhibitor beta rho GDP-dissociation Inhibitor 2 X69549 NM_001175 1984_s_at P P 1.7 0.163 2.4 KIAA0975, imidazoline receptor AB023192 NM_007184 33916_at P A 1.7 0.343 candidate poliovirus receptor X64116 NM_006505 32698_at P P 1.7 0.173 poliovirus receptor X64116 NM_006505 32699_s_at P P 1.3 0.102 immediate early response 3 S81914 NM_003897 1237_at P P 1.7 0.171 metallothionein 2A AI547258 NM_005953 39081_at P A 1.7 0.247 tropomyosin 1 (alpha) M19267 NM_000366 36791_g_at P P 1.6 0.184 1.0 tropomyosin 1 (alpha) Z24727 NM_000366 36792_at P P 1.4 0.094 1.3 tropomyosin 1 (alpha) M19267 NM_000366 36790_at P P 1.2 0.213 TRAM-like protein D31762 NM_012288 40051_at P P 1.6 0.244 1.1 E3 ubiquitin ligase SMURF2 AA630312 NM_022739 33354_at P P 1.6 0.244 2.2 EGF-containing fibulin-like U03877 NM_004105 32551_at P P 1.6 0.152 extracellular matrix protein 1 G protein-coupled receptor 56 AJ011001 NM_005682 35769_at P P 1.6 0.075 c-jun proto oncogene (JUN) J04111 NM_002228 32583_at P A 1.6 0.377 regulator of G-protein signalling 10, AF045229 NM_002925 33121_g_at P A 1.6 0.064 RGS10 amyloid beta (A4) precursor U62325 40148_at P P 1.6 0.312 1.3 protein-binding, family B, member 2 (Fe65-like) ras-related rho protein M12174 NM_004040 1826_at P P 1.6 0.281 1.4 proteasome (prosome, macropain) AL031177 NM_002814 37957_at P A 1.5 0.265 26S subunit, non-ATPase, 10 KIAA0537 AB011109 NM_014840 33787_at P P 1.5 0.135 1.8 lysosome-associated membrane X77196 NM_002294 38403_at P P 1.5 0.432 protein-2 phospholipid transfer protein L26232 NM_006227 40081_at P P 1.5 0.046 N-myristoyltransferase 2 AF043325 NM_004808 41656_at P P 1.5 0.038 phosphofructokinase (PFKM) U24183 NM_000289 36196_at P P 1.5 0.374 2.0 integrin, beta 4 X53587 NM_000213 406_at P A 1.5 0.195 leupaxin AF062075 NM_004811 36062_at P A 1.5 0.231 1.3 endothelin-converting-enzyme 1 Z35307 NM_001397 41726_at P P 1.5 0.180 wild-type p53 activated fragment-1 U03106 NM_000389 2031_s_at P P 1.5 0.399 (WAF1), cyclin-dependent kinase inhibitor 1A (p21, Cip1) ICAM-2, cell adhesion ligand for X15606 NM_000873 38453_at P P 1.5 0.024 1.5 LFA-1 ICAM-2, cell adhesion ligand for X15606 NM_000873 38454_g_at P P 1.5 0.153 2.0 LFA-1 intercellular adhesion molecule 2 M32334 590_at P P 1.4 0.152 1.5 (ICAM-2) eukaryotic translation initiation AF035280 NM_014239 40515_at P P 1.5 0.108 factor 2B, eIF-2B beta subunit uridine phosphorylase X90858 NM_003364 37351_at P M 1.5 0.064 integrin, beta 5 X53002 NM_002213 39754_at P P 1.5 0.068 N-sulfoglucosamine sulfohydrolase U30894 NM_000199 35626_at P P 1.5 0.077 (sulfamidase) synaptojanin 2 AF039945 36532_at P A 1.5 0.164 1.1 metallothionein 1L AA224832 NM_002450 39120_at P A 1.4 0.664 macrophage capping protein, M94345 NM_001747 38391_at P P 1.4 0.281 gelsolin-like HSPC022 protein W68830 NM_014029 32736_at P P 1.4 0.062 2.7 Human clone 137308 mRNA, AW006742 38207_at P A 1.4 0.442 partial cds protocadherin 42, PC42, L11370 NM_002587 37562_at P A 1.4 0.166 protocadherin 1 (cadherin-like 1) caspase-like apoptosis regulatory AF005775 NM_003879 1867_at P P 1.4 0.363 1.5 protein 2 (CLARP2) caspase-like apoptosis regulatory AF005775 NM_003879 1868_g_at P P 1.2 0.325 2.2 protein 2 (CLARP2) major vault protein, lrp X79882 NM_005115 38064_at P P 1.4 0.252 1.0 Fanconi anemia, complementation AC004472 NM_004629 33842_at P A 1.4 0.233 group G prion protein (PrP) U29185 NM_000311 36159_s_at P P 1.4 0.342 1.1 interferon-stimulated protein, 15 kDa AA203213 NM_005101 38432_at P A 1.4 0.244 serine (or cysteine) proteinase L40377 NM_002640 36312_at P A 1.3 0.360 2.2 inhibitor, clade B (ovalbumin), cytoplasmic antiproteinase 2 (CAP2) biglycan J04599 NM_001711 38126_at P P 1.3 0.101 chemokine (C—X—C motif), L06797 NM_003467 649_s_at P P 1.3 0.177 + receptor 4 (fusin) ubiquitin carboxyl-terminal esterase X04741 NM_004181 36990_at P P 1.3 0.117 L1 (ubiquitin thiolesterase) KIAA0469 AB007938 NM_014851 37230_at P P 1.3 0.124 TNF (ligand) superfamily, member AL022310 NM_003326 32319_at P A 1.3 0.349 4 (tax-transcriptionally activated glycoprotein 1, 34 kD) KIAA1053 AB028976 40855_at P P 1.3 0.242 1.6 NAD(P)H-quinone oxireductase M81600 38066_at P P 1.3 0.058 1.8 sushi-repeat-containing protein U61374 NM_006307 31855_at P P 1.3 0.610 1.2 integrin, alpha 5 X06256 NM_002205 39753_at P P 1.3 0.179 + 1.2 enigma (LIM domain protein) L35240 NM_005451 39530_at P P 1.3 0.396 ectonucleoside triphosphate AJ133133 NM_001776 32826_at P A 1.3 0.412 1.5 diphosphohydrolase 1 transforming growth factor-beta M60315 NM_001718 39279_at P P 1.3 0.206 (tgf-beta), bone morphogenetic protein 6 transforming growth factor-beta M60315 NM_001718 1733_at P P 1.0 0.308 (tgf-beta), bone morphogenetic protein 6 nicotinamide N-methyltransferase, U08021 NM_006169 37032_at P P 1.2 0.083 2.1 NNMT cDNA DKFZp564J0323 (from AL049957 39170_at P P 1.2 0.264 1.2 clone DKFZp564J0323) thioredoxin reductase beta AB019694 NM_006440 41711_at P A 1.2 0.206 f-box and leucine-rich repeat AL049953 36525_at P A 1.2 0.300 1.2 protein 2 transcobalamin II (TCN2) L02648 NM_000355 37922_at P A 1.2 0.342 1.2 aldehyde dehydrogenase 2, X05409 NM_000690 32747_at P P 1.2 0.117 mitochondrial GTP-binding protein ragB X90530 NM_006064 39989_at P M 1.2 0.602 lymphocyte antigen 75 AF011333 NM_002349 38160_at P A 1.2 0.132 1.7 GM2 activator protein X62078 35820_at P P 1.2 0.101 1.5 type 3 inositol 1,4,5-trisphosphate U01062 NM_002224 182_at P P 1.2 0.052 1.5 receptor (ITPR3) KIAA0284 AI828210 38592_s_at P P 1.2 0.078 1.9 metallothionein I-B M13485 609_f_at P P 1.2 0.266 BTG2 U72649 NM_006763 36634_at P P 1.2 0.210 adenylate kinase 1 J04809 NM_000476 36997_at P A 1.2 0.246 tumor necrosis factor receptor Y09392 NM_003790 41189_at P P 1.2 0.350 superfamily, member 12, WSL-LR, WSL-S1 and WSL-S2 proteins aminopeptidase N/CD13 M22324 NM_001150 39385_at P P 1.2 0.398 growth arrest and DNA-damage- M60974 NM_001924 1911_s_at P P 1.2 0.177 inducible protein (gadd45) KIAA0638 protein AB014538 37375_at P P 1.2 0.680 vinculin M33308 NM_003373 36601_at P P 1.2 0.078 + procollagen-proline, 2-oxoglutarate U90441 NM_004199 34390_at P P 1.1 0.347 4-dioxygenase (proline 4- U65093 NM_006079 33113_at P P 1.1 0.164 1.2 hydroxylase), alpha polypeptide II msg1-related gene 1 (mrg1), Cbp/p300-interacting transactivator microsomal glutathione S- AF026977 NM_004528 39018_at P P 1.1 0.191 1.1 transferase 3 vitamin A responsive; cytoskeleton AF070523 NM_006407 39091_at P P 1.1 0.216 2.9 related 17-kDa protein, interferon- M13755 NM_005101 1107_s_at P P 1.1 0.119 stimulated protein, 15 kDa matrix metalloproteinase 14 X83535 NM_004995 34747_at P A 1.1 0.487 2.4 (membrane-inserted) 4F2 cell-surface antigen, solute J02939 NM_002394 38029_at P P 1.1 0.143 carrier family 3, member 2 metallothionein-III M93311 NM_005954 870_f_at P P 1.1 0.334 protein kinase (cAMP-dependent, S76965 NM_006823 36202_at P P 1.1 0.046 catalytic) inhibitor alpha protein kinase (cAMP-dependent, S76965 NM_006823 546_at P P 1.0 0.367 catalytic) inhibitor alpha reticulocalbin 1, EF-hand calcium D42073 NM_002901 40556_at P P 1.1 0.035 1.1 binding domain lipin 1, KIAA0188 D80010 38098_at P P 1.1 0.080 1.4 protease, serine, 23 AF015287 NM_007173 40078_at P P 1.0 0.099 1.3 hect domain and RLD 2 AF041080 NM_004667 40877_s_at P P 1.0 0.104 GATA-binding protein (GATA2) M68891 NM_002050 37194_at P P 1.0 0.325 1.0 agrin precursor AF016903 33454_at P P 1.0 0.272 equilibrative nucleoside transporter U81375 NM_004955 33901_at P P 1.0 0.352 1 (hENT1) coronin, actin-binding protein 2B, AB023142 34772_at P A 1.0 0.459 KIAA0925 f-box and WD-40 domain protein 3 U07000 NM_012165 537_f_at P M 1.0 0.212 nonsyndromic hearing impairment AF073308 NM_004403 41872_at P P 1.0 0.535 1.0 protein (DFNA5) actin filament associated protein D25248 NM_021638 37578_at P P 1.0 0.218 TNFR-related death receptor-6 AF068868 NM_014452 35402_at P A 1.0 0.235 1.7 (DR6) serum/glucocorticoid regulated Y10032 NM_005627 973_at P A 1.0 0.174 kinase DNase X X90392 NM_006730 37214_g_at P P 1.0 0.507 DNase X X90392 NM_006730 37213_at P P 1.0 0.376 fatty acid desaturase 3 AC004770 NM_021727 34224_at P P 1.0 0.294 LYL-1 M22637 39971_at P P 1.0 0.313 1.4 ATP-binding cassette, sub-family C X78338 NM_004996 34016_s_at P A 1.0 0.258 2.3 (CFTR/MRP), member 1 transmembrane protein (CD59) M84349 39351_at P P 1.0 0.141 1.1 fms-related tyrosine kinase 1, S77812 NM_002019 1545_g_at P P 1.0 0.535 + 1.9 VEGFR-1 ¹A measurement indicating whether the transcript was detected (present, P), not detected (absent, A) or marginally detected (marginal, M; also if P in one experiment but A in another) ²The change in expression level for a transcript between two independently harvested BECs and LECs (=total of 4 comparisons). The change is expressed as the log2 ratio. ³Standard deviation of the change in the expression level (in 4 comparisons) NB = Northern blot, IF = immunofluorescence

TABLE 10 Known LEC-specific genes Accession numbers Gene Detection* starting EST possible gene CD36 = Af (S/4, 3) R20784 M98399 COL1/TSP receptor, fatty-acid transport H54254 protein beta1-syntrophin Af (S/4, 5) AA447177 L31529 collectin sub-family member 12 Af (S/4, 5) R74387 NM_030781 a disintegrin and metalloprotease Af (S/4, 3) AA147933 NM_003474 domain 12 cytotoxic T-lymphocyte- Af (S/4, 0) AI733018 NM_005214 associated protein 4 niban protein NM_022083 niban Af (S/3, 7) AA554814 NM_052966 protein multi-PDZ-domain-containing Af (S/3, 5) AI738919 NM_032622 protein, LNX MAGE-E1 protein Af (S/3, 2) AI435112 NM_030801 upstream stimulatory factor 1, Af (S/2, 6) AA701033 AB017568 USF1 (genomic match) hairy/enhancer-of-split related Af (NS/2, 6) R61374 NM_012258 with YRPW motif 1 alpha-2,8-polysialyltransferase Af (S/2, 5) AI422986 L41680 semaphorin 6A1 Af (S/2, 4) W21965 NM_020796 guanine nucleotide binding Af (S/2, 3) AA738022 protein (G prot), gamma 2 integral membrane protein 3 Af (S/2, 3) AA128019 NM_030926 similar to mouse glucocorticoid- Af (S/2, 0) AI678080 XM_070471 induced gene 1 YAP65 (Yes-associated protein of Af (NS/2, 0) AL048399 X80507 65 kDa MW) 17 kDa fetal brain protein Af (NS/1, 9) H92988 NM_022343 Kruppel-like factor 5 Af (S/1, 8) AI815057 NM_001730 calcitonin receptor-like, CGRP Af (S/1, 7) AI741128, NM_005795, L76380 type 1 receptor T94540 fibroblast growth factor 13, Af (NS/1, 7) AW014749 NM_004114 isoform 1A tetraspan NET-6 protein Af (NS/1, 6) W22687 NM_014399 ring finger protein 11 Af (S/1, 6) AL079648 BC020964 *Af = Affymetrix, S = specific for LEC, NS = nonspecific (also expressed in BEC), numbers represent log2 ratio of the signal intensities between BEC and LEC

TABLE 11 Differentially expressed genes identified by accession number Gene Detection* starting EST SEQ ID NO: EST Af (S/4, 9) AL079386 1 EST Af (S/3, 7) N21555 2 EST Af (S/3, 2) AL119027 3 EST Af (S/2, 9) H05299 4 EST Af (S/2, 8) AA973128 5 EST Af (NS/2, 6) AI128820 EST Af (S/2, 3) AW044647 6 EST Af (S/2, 2) AI333058 7 EST Af (S/2, 1) AI536067 8 EST Af (NS/2, 0) AA156409 EST Af (S/1, 9) AI770080 9 EST Af (NS/1, 9) AA456099 EST Af (S/1, 8) AI692645 10 EST Af (S/1, 7) AL119265 11 EST Af (S/1, 6) AI478114 12 EST Af (S/1, 6) AI817448 13 *Af = Affymetrix, S = specific for LEC, NS = nonspecific (also expressed in BEC), numbers represent log2 ratio of the signal intensities between BEC and LEC

TABLE 12 Other Proteins Identified Accession numbers Gene Detection* starting EST possible gene KIAA1392, hypothetical protein Af (S/5, 3) N50545 XM_048721 (20) DKFZp762K222 similar to phosphoglucomutase 5 Af (S/4, 5) AL046941 XM_047649 (21) Similar to transmembrane receptor Unc5H1 Af (S/4, 5) R56359 XM_030300 (22) hypothetical protein MGC21854 Af (S/3, 7) AI659418 NM_052862 (23) KIAA1877 Af (S/3, 4) AW004016 similar to unnamed protein product Af (NS/3, 1) AA036952 XM_085235 unknown protein Af (S/2, 9) AA846091 XM_038314 (24) KIAA1058 (+missing N-term Af (S/2, 6) AA007697 AB028981 (25) from ests) similar to KIAA1673 Af (S/2, 3) AI948598 XM_059607 (26) similar to lysosomal amino acid Af (S/2, 3) AI692279 XM_058449 (27) transporter 1 Homo sapiens similar to KIAA1673 protein Af (S/2, 3) AI948598 XM_059607 KIAA0493 Af (S/2, 3) AA532655 AB007962 (28) hypothetical protein MGC2780 Af (S/2, 3) AI734962 NM_025266 (29) transmembrane protein 2 Af (NS/2, 3) NM_013390 57094_at Novel human gene mapping to Af (S/2, 2) AA651889 HS455J72 (30) chomosome 1 *Af = Affymetrix, S = specific for LEC, NS = nonspecific (also expressed in BEC), numbers represent log2 ratio of the signal intensities between BEC and LEC

In Tables 5, 6 and 12, the numbers in parentheses refer to the SEQ ID NO: in the Sequence Listing. Table 13 below correlates these sequences with polypeptide sequences SEQ ID NO:31-44 and 46 (Open reading frames, ORF's). TABLE 13 Polypeptides corresponding to LEC-specific polynucleotides Accession number Polynucleotide Polypeptide NM_021647 SEQ ID NO: 14 SEQ ID NO: 31 NM_014817 SEQ ID NO: 15 SEQ ID NO: 32 XM_059074 SEQ ID NO: 16 SEQ ID NO: 33 NM_016647 SEQ ID NO: 17 SEQ ID NO: 34 XM_048721 SEQ ID NO: 20 SEQ ID NO: 35 XM_047649 SEQ ID NO: 21 SEQ ID NO: 36 XM_030300 SEQ ID NO: 22 SEQ ID NO: 37 NM_052862 SEQ ID NO: 23 SEQ ID NO: 38 XM_039314 SEQ ID NO: 24 SEQ ID NO: 39 AB028981 SEQ ID NO: 25 SEQ ID NO: 40 XM_059607 SEQ ID NO: 26 SEQ ID NO: 41 XM_058449 SEQ ID NO: 27 SEQ ID NO: 42 NM_025266 SEQ ID NO: 29 SEQ ID NO: 43 AL137762/HS455J72 SEQ ID NO: 30 SEQ ID NO: 44 XM_084655 SEQ ID NO: 45 SEQ ID NO: 46

TABLE 14 Sequence identifiers for sequences in Table 3 accession numbers aa SEQ ID NO: nt SEQ ID NO: lung type-I cell membrane-associated protein, AF030428 NM_006474 SEQ ID NO: 65 SEQ ID NO: 66 podoplanin lung type-I cell membrane-associated protein, AI660929 NM_006474 duplicate podoplanin cellular retinol-binding protein M11433 NM_002899 SEQ ID NO: 67 SEQ ID NO: 68 macrophage mannose receptor (MRC1) M93221 SEQ ID NO: 69 SEQ ID NO: 70 transcription factor C-MAF AF055376 NM_005360 SEQ ID NO: 71 SEQ ID NO: 72 transcription factor C-MAF AF055376 NM_005360 duplicate selenoprotein P Z11793 NM_005410 SEQ ID NO: 73 SEQ ID NO: 74 KIAA0466, immunoglobulin superfamily, AB007935 NM_001542 SEQ ID NO: 75 SEQ ID NO: 76 member 3 type II membrane protein similar to HIV gp120- AB015629 NM_014257 SEQ ID NO: 77 SEQ ID NO: 78 binding C-type lectin, CD209 antigen-like KIAA0626 AB014526 NM_021647 SEQ ID NO: 79 SEQ ID NO: 80 KIAA0711 AB018254 NM_014867 SEQ ID NO: 81 SEQ ID NO: 82 integrin alpha 9 D25303 NM_002207 SEQ ID NO: 83 SEQ ID NO: 84 integrin alpha 9 D25303 NM_002207 duplicate relaxin H2 X00948 NM_005059 SEQ ID NO: 85 SEQ ID NO: 86 KIAA0644 AB014544 NM_014817 SEQ ID NO: 87 SEQ ID NO: 88 Cdk-inhibitor p57KIP2 (KIP2) U22398 NM_000076 SEQ ID NO: 89 SEQ ID NO: 90 Cdk-inhibitor p57KIP2 (KIP2) U22398 NM_000076 duplicate transient receptor potential channel TRPC6 AJ006276 NM_004621 SEQ ID NO: 91 SEQ ID NO: 92 cDNA DKFZp564O222 (from clone AL050002 SEQ ID NO: 93 DKFZp564O222) M80482 NM_002570 SEQ ID NO: 94 SEQ ID NO: 95 regulator of G-protein signalling 16, A28-RGS14p U70426 NM_002928 SEQ ID NO: 96 SEQ ID NO: 97 dihydropyrimidinase related protein-1, collapsin D78012 NM_001313 SEQ ID NO: 98 SEQ ID NO: 99 response mediator protein 1 desmoplakin (DPI, DPII) AL031058 NM_004415 SEQ ID NO: 100 SEQ ID NO: 101 pendrin, solute carrier family, member 4 AF030880 NM_000441 SEQ ID NO: 102 SEQ ID NO: 103 reelin (RELN) U79716 NM_005045 SEQ ID NO: 104 SEQ ID NO: 105 integrin, alpha 1 X68742 SEQ ID NO: 106 integrin alpha 1 X68742 duplicate cholesterol 25-hydroxylase AF059214 NM_003956 SEQ ID NO: 107 SEQ ID NO: 108 inhibin beta-B-subunit precursor M31682 NM_002193 SEQ ID NO: 109 SEQ ID NO: 110 KIAA1233 AL109724 pre-B cell stimulating factor homologue (SDF1b) L36033 NM_000609 SEQ ID NO: 112 SEQ ID NO: 113 V-Erba Related Ear-3 Protein HG3510-HT3704 SEQ ID NO: 114 antigen identified by monoclonal antibody MRC X05323 SEQ ID NO: 115 SEQ ID NO: 116 OX-2 apolipoprotein D J02611 NM_001647 SEQ ID NO: 117 SEQ ID NO: 118 TIMP3, tissue inhibitor of matrix U14394 NM_000362 SEQ ID NO: 119 SEQ ID NO: 120 metalloproteinases TIMP3 U14394 NM_000362 duplicate aldehyde dehydrogenase 1 K03000 NM_000689 SEQ ID NO: 121 SEQ ID NO: 122 prospero-related homeobox 1 (prox 1) U44060 NM_002763 SEQ ID NO: 123 SEQ ID NO: 124 matrix Gla protein AI953789 NM_000900 SEQ ID NO: 125 SEQ ID NO: 126 neuronal pentraxin II (NPTX2) U29195 SEQ ID NO: 127 SEQ ID NO: 128 histatin 2 (HIS2) M26665 NM_000200 SEQ ID NO: 129 SEQ ID NO: 130 ADDL mRNA for adducin-like protein, adducin 3 D67031 NM_016824 SEQ ID NO: 131 SEQ ID NO: 132 (gamma) adducin 3 (gamma) U37122 NM_016824 duplicate MADS box transcription enhancer factor 2, L08895 NM_002397 SEQ ID NO: 133 SEQ ID NO: 134 polypeptide C (myocyte enhancer factor 2C) MADS box transcription enhancer factor 2, NM_002397 duplicate (myocyte enhancer factor 2C) MADS box transcription enhancer factor 2, S57212 NM_002397 duplicate polypeptide C (myocyte enhancer factor 2C) phosphoglucomutase 5 L40933 NM_021965 SEQ ID NO: 135 SEQ ID NO: 136 cyclin E2 AF102778 NM_004702 SEQ ID NO: 137 SEQ ID NO: 138 interleukin 7 (IL7) M29053 SEQ ID NO: 139 SEQ ID NO: 140 interleukin 7 J04156 NM_000880 duplicate cDNA DKFZp586L0120 (from clone AL050154 SEQ ID NO: 141 DKFZp586L0120) peroxisome proliferative activated receptor, L40904 NM_005037 SEQ ID NO: 142 SEQ ID NO: 143 gamma, PPARG fatty acid binding protein 4 AA128249 NM_001442 SEQ ID NO: 144 SEQ ID NO: 145 protein kinase C zeta Z15108 NM_002744 SEQ ID NO: 146 SEQ ID NO: 147 46 kDa coxsackievirus and adenovirus receptor Y07593 NM_001338 SEQ ID NO: 148 SEQ ID NO: 149 (CAR) protein PAC clone RP4-751H13 from 7q35-qter, zinc AC004877 SEQ ID NO: 150 SEQ ID NO: 151 finger-like thymidine kinase 1, soluble M15205 NM_003258 SEQ ID NO: 152 SEQ ID NO: 153 thymidine kinase 1 K02581 NM_003258 duplicate Pig7 (PIG7), LPS-induced TNF-alpha factor AF010312 NM_004862 SEQ ID NO: 154 SEQ ID NO: 155 LPS-induced TNF-alpha factor AL120815 NM_004862 duplicate lipase A, lysosomal acid, cholesterol esterase X76488 NM_000235 SEQ ID NO: 156 SEQ ID NO: 157 ubiquitin specific protease 13 (isopeptidase T-3) U75362 NM_003940 SEQ ID NO: 158 SEQ ID NO: 159 carcinoembryonic antigen-related cell adhesion X16354 NM_001712 SEQ ID NO: 160 SEQ ID NO: 161 molecule 1 (biliary glycoprotein) CEACAM1 cDNA DKFZp586D0918 (from clone AL049370 SEQ ID NO: 162 DKFZp586D0918) KIAA0598, B cell RAG associated protein AB011170 NM_014863 SEQ ID NO: 163 SEQ ID NO: 164 RAMP2 (receptor (calcitonin) activity modifying AJ001015 NM_005854 SEQ ID NO: 165 SEQ ID NO: 166 protein 2) cholesteryl ester transfer protein precursor M30185 NM_000078 SEQ ID NO: 167 SEQ ID NO: 168 epithelial membrane protein 2 U52100 NM_001424 SEQ ID NO: 169 SEQ ID NO: 170 MHC class II lymphocyte antigen (HLA-DP) beta M83664 NM_002121 SEQ ID NO: 171 SEQ ID NO: 172 chain MHC class II lymphocyte antigen (HLA-DP) beta M83664 NM_002121 duplicate chain beta-arrestin 2 AF106941 NM_004313 SEQ ID NO: 173 SEQ ID NO: 174 mitotic checkpoint kinase Bub1 (BUB1) AF053305 NM_004336 SEQ ID NO: 175 SEQ ID NO: 176 KIAA0229, similar to human ankyrin 1(S08275) D86982 SEQ ID NO: 177 SEQ ID NO: 178 Sprouty 1 homolog (antagonist of FGF signaling) AF041037 SEQ ID NO: 179 SEQ ID NO: 180 guanine nucleotide exchange factor for Rap1; M- NM_012294 SEQ ID NO: 181 SEQ ID NO: 182 Ras-regulated GEF, KIAA0277 translin X78627 NM_004622 SEQ ID NO: 183 SEQ ID NO: 184 erythrocyte membrane protein band 4.9 (dematin) U28389 NM_001978 SEQ ID NO: 185 SEQ ID NO: 186 KIAA0846 protein AB020653 NM_015376 SEQ ID NO: 187 SEQ ID NO: 188 glia maturation factor, gamma W07033 NM_004877 SEQ ID NO: 189 SEQ ID NO: 190 insulin-like growth factor binding protein 2 X16302 NM_000597 SEQ ID NO: 191 SEQ ID NO: 192 (IGFBP-2) smooth muscle myosin heavy chain isoform S67247 SEQ ID NO: 193 SEQ ID NO: 194 Smemb TTG-2 (cysteine rich protein with LIM motif), X61118 NM_005574 SEQ ID NO: 195 SEQ ID NO: 196 LIM domain only 2 (rhombotin-like 1) cyclin B2 AL080146 NM_004701 SEQ ID NO: 197 SEQ ID NO: 198 KIAA0353 AB002351 SEQ ID NO: 199 SEQ ID NO: 200 KIAA0559, piccolo (presynaptic cytomatrix AB011131 SEQ ID NO: 201 SEQ ID NO: 202 G protein-coupled receptor, family C, group 5, AC004131 NM_016235 SEQ ID NO: 203 SEQ ID NO: 204 G protein-coupled receptor, family C, group 5, AI801872 NM_016235 duplicate dup member B CREM (cyclic AMP-responsive element S68134 NM_001881 SEQ ID NO: 205 SEQ ID NO: 206 modulator beta isoform) CREM (cyclic AMP-responsive element S68134 NM_001881 duplicate dup modulator beta isoform) CREM (cyclic AMP-responsive element S68271 NM_001881 duplicate dup modulator beta isoform) hypothetical protein FLJ13110 AL080222 NM_022912 SEQ ID NO: 207 SEQ ID NO: 208 inositol(myo)-1(or 4)-monophosphatase 2 AF014398 NM_014214 SEQ ID NO: 209 SEQ ID NO: 210 KIAA0937 protein AB023154 SEQ ID NO: 211 SEQ ID NO: 212 mitotic spindle coiled-coil related protein AF063308 NM_006461 SEQ ID NO: 213 SEQ ID NO: 214 cysteine and glycine-rich protein 2 (CSRP2) U57646 NM_001321 SEQ ID NO: 215 SEQ ID NO: 216 topoisomerase (DNA) II alpha (170 kD) AI375913 NM_001067 SEQ ID NO: 217 SEQ ID NO: 218 DNA topoisomerase II J04088 NM_001067 duplicate dup protein phosphatase inhibitor 2 (PPP1R2) U68111 SEQ ID NO: 219 SEQ ID NO: 220 KIAA0186 D80008 NM_021067 SEQ ID NO: 221 SEQ ID NO: 222 dual-specificity tyrosine-(Y)-phosphorylation Y12735 NM_003582 SEQ ID NO: 223 SEQ ID NO: 224 regulated kinase 3 (Dyrk3) kinesin-like spindle protein HKSP (HKSP) U37426 NM_004523 SEQ ID NO: 225 SEQ ID NO: 226 huntingtin-associated protein interacting protein U94190 NM_003947 SEQ ID NO: 227 SEQ ID NO: 228 (duo) diubiquitin AL031983 NM_006398 SEQ ID NO: 229 SEQ ID NO: 230 bikunin, serine protease inhibitor, Kunitz type, 2 U78095 NM_021102 SEQ ID NO: 231 SEQ ID NO: 232 cytochrome P-450-1 (TCDD-inducible) K03191 NM_000499 SEQ ID NO: 233 SEQ ID NO: 234 cytochrome P(1)-450 X02612 NM_000499 duplicate dup KIAA0513 NM_014732 SEQ ID NO: 235 SEQ ID NO: 236 protein phosphatase inhibitor 2 (PPP1R2) U68111 duplicate RAMP3 (receptor (calcitonin) activity modifying AJ001016 NM_005856 SEQ ID NO: 237 SEQ ID NO: 238 protein 3) B-myb X13293 NM_002466 SEQ ID NO: 239 SEQ ID NO: 240 KIAA0952 AB023169 NM_014962 SEQ ID NO: 241 SEQ ID NO: 242 interferon stimulated gene (20 kD), HEM45 U88964 NM_002201 SEQ ID NO: 243 SEQ ID NO: 244 GS3955 D87119 NM_021643 SEQ ID NO: 245 SEQ ID NO: 246 GS3955 D87119 NM_021643 duplicate dup GRB2-related adaptor protein (Grap) U52518 NM_006613 SEQ ID NO: 247 SEQ ID NO: 248 KIAA1071 protein AB028994 SEQ ID NO: 249 SEQ ID NO: 250 RNA-binding protein gene with multiple splicing, D84111 NM_006867 SEQ ID NO: 251 SEQ ID NO: 252 RBP-MS/type 5 RNA-binding protein gene with multiple splicing, D84111 NM_006867 duplicate dup RBP-MS/type 5 RBP-MS/type 4, RNA-binding protein gene with D84110 NM_006867 duplicate multiple splicing RBP-MS/type 4, RNA-binding protein gene with D84110 NM_006867 duplicate dup multiple splicing RBP-MS/type 3, RNA-binding protein gene with D84109 NM_006867 duplicate dup multiple splicing alpha-actinin-2-associated LIM protein AF002282 NM_014476 SEQ ID NO: 253 SEQ ID NO: 254 semaphorin-III (Hsema-I), semaphorin 3A L26081 NM_006080 SEQ ID NO: 255 SEQ ID NO: 256 IQ motif containing GTPase activating protein 2 U51903 NM_006633 SEQ ID NO: 257 SEQ ID NO: 258 Arrestin, Beta 2 HG2059-HT2114 duplicate retinoblastoma-associated protein HEC AF017790 NM_006101 SEQ ID NO: 259 SEQ ID NO: 260 LIM domain binding protein (LDB1) AF052389 NM_001290 SEQ ID NO: 261 SEQ ID NO: 262 dual specificity phosphatase 5 U15932 NM_004419 SEQ ID NO: 263 SEQ ID NO: 264 Homo sapiens cDNA 3′, mRNA sequence AI557322 SEQ ID NO: 265 monoamine oxidase A (MAOA) M68840 NM_000240 SEQ ID NO: 266 SEQ ID NO: 267 monoamine oxidase A AA420624 NM_000240 duplicate NECDIN related protein U35139 NM_002487 SEQ ID NO: 268 SEQ ID NO: 269 regulatory solute carrier protein, family 1, X82877 NM_006511 SEQ ID NO: 270 SEQ ID NO: 271 member 1 TTK protein kinase M86699 NM_003318 SEQ ID NO: 272 SEQ ID NO: 273 fms-related tyrosine kinase 4, VEGFR-3 X69878 NM_002020 SEQ ID NO: 274 SEQ ID NO: 275 TSC403, similar to lysosome-associated AB013924 NM_014398 SEQ ID NO: 276 SEQ ID NO: 277 membrane glycoprotein HMG-2 X62534 SEQ ID NO: 278 SEQ ID NO: 279 Homo sapiens clone 24416 mRNA sequence AF052159 SEQ ID NO: 280 SEQ ID NO: 281 calcitonin receptor-like L76380 NM_005795 SEQ ID NO: 282 SEQ ID NO: 283 KIAA0582 protein AI761647 NM_015147 SEQ ID NO: 284 SEQ ID NO: 285 cDNA DKFZp434B102 (from clone AL080192 SEQ ID NO: 286 DKFZp434B102) cDNA DKFZp586G1922 (from clone AL080110 SEQ ID NO: 287 SEQ ID NO: 287 DKFZp586G1922) Acyl-CoA synthetase 3 D89053 NM_004457 SEQ ID NO: 288 SEQ ID NO: 289 fatty-acid-Coenzyme A ligase, long-chain 3 AA977580 NM_004457 duplicate STAT induced STAT inhibitor-2 AF037989 SEQ ID NO: 290 SEQ ID NO: 291 Homeotic Protein Hox5.4 HG3502-HT3696 SEQ ID NO: 292 hypothetical protein FLJ13910, cDNA AL050139 NM_022780 SEQ ID NO: 293 SEQ ID NO: 294 DKFZp586M141 (from clone DKFZp586M141) cDNA DKFZp586N012 (from clone AL049471 SEQ ID NO: 295 DKFZp586N012) UbcH10, ubiquitin carrier protein E2-C U73379 NM_007019 SEQ ID NO: 296 SEQ ID NO: 297 cyclin-dependent kinase inhibitor 3, protein L25876 NM_005192 SEQ ID NO: 298 SEQ ID NO: 299 tyrosine phosphatase (CIP2) glycogen phosphorylase (PYGL) AF046798 SEQ ID NO: 300 SEQ ID NO: 301 Angiopoietin-2 AF004327 NM_001147 SEQ ID NO: 302 SEQ ID NO: 303 Angiopoietin-2 AF004327 NM_001147 duplicate dup forkhead box M1 U74612 NM_021953 SEQ ID NO: 304 SEQ ID NO: 305 potentially prenylated protein tyrosine AF041434 NM_007079 SEQ ID NO: 306 SEQ ID NO: 307 phosphatase hPRL-3 RAB31, Low Mr GTP-binding protein of the Rab U59877 NM_006868 SEQ ID NO: 308 SEQ ID NO: 309 subfamily RAB31, member RAS oncogene family AI189226 NM_006868 myosin VIIA U39226 NM_000260 SEQ ID NO: 310 SEQ ID NO: 311 Grb2-associated binder-1, docking protein related U43885 NM_002039 SEQ ID NO: 312 SEQ ID NO: 313 to IRS-1 lamin B1 L37747 SEQ ID NO: 314 SEQ ID NO: 315 minichromosome maintenance deficient (mis5, S. pombe) D84557 NM_005915 SEQ ID NO: 316 SEQ ID NO: 317 6 HsMcm6 cyclin B1 M25753 SEQ ID NO: 318 cyclin B1 M25753 duplicate dup RTP, N-myc downstream regulated D87953 NM_006096 SEQ ID NO: 319 SEQ ID NO: 320 alpha2,3-sialyltransferase AB022918 NM_006100 SEQ ID NO: 321 SEQ ID NO: 322 ADP-ribosylation factor-like protein 4 U73960 NM_005738 SEQ ID NO: 323 SEQ ID NO: 324 centromere protein F (350/400 kD, mitosin) U30872 NM_016343 SEQ ID NO: 325 SEQ ID NO: 326 paternally expressed 10, KIAA1051 AB028974 NM_015068 SEQ ID NO: 327 SEQ ID NO: 328 tubulin, alpha 1 (testis specific) X06956 SEQ ID NO: 329 SEQ ID NO: 330 KIAA0101 D14657 NM_014736 SEQ ID NO: 331 SEQ ID NO: 332 KIAA0128, septin 2 D50918 SEQ ID NO: 333 SEQ ID NO: 334 protein phosphatase 2, regulatory subunit B (B56), Z69030 NM_002719 SEQ ID NO: 335 SEQ ID NO: 336 gamma deoxycytidine kinase M60527 NM_000788 SEQ ID NO: 337 SEQ ID NO: 338 integrin beta 3 binding protein (beta3-endonexin) U37139 NM_014288 SEQ ID NO: 339 SEQ ID NO: 340 TAL1 (SCL) interrupting locus M74558 NM_003035 SEQ ID NO: 341 SEQ ID NO: 342 KIAA0666 AB014566 SEQ ID NO: 343 SEQ ID NO: 344 cAMP-specific phosphodiesterase 8A, PDE8A1 AF056490 SEQ ID NO: 345 SEQ ID NO: 346 mitotic checkpoint kinase Mad3L (MAD3L), AF053306 NM_001211 SEQ ID NO: 347 SEQ ID NO: 348 BUB1B ribosomal S6 kinase X85106 NM_021135 SEQ ID NO: 349 SEQ ID NO: 350 HPTP epsilon (protein tyrosine phosphatase X54134 NM_006504 SEQ ID NO: 351 SEQ ID NO: 352 epsilon) Lyn tyrosine kinase, v-yes-1 Yamaguchi sarcoma M79321 NM_002350 SEQ ID NO: 353 SEQ ID NO: 354 viral related oncogene homolog lyn tyrosine kinase, v-yes-1 Yamaguchi sarcoma M16038 NM_002350 duplicate viral related oncogene homolog lyn tyrosine kinase M16038 NM_002350 duplicate brachyury variant A (TBX1), T-box 1 AF012130 NM_005992 SEQ ID NO: 355 SEQ ID NO: 356 transcription factor mki67a mRNA (long type) for antigen of X65550 NM_002417 SEQ ID NO: 357 SEQ ID NO: 358 monoclonal antibody Ki-67 protein tyrosine phosphatase receptor pi (PTPRP) U81561 NM_002847 SEQ ID NO: 359 SEQ ID NO: 360 cb1-b U26710 NM_004351 SEQ ID NO: 361 SEQ ID NO: 362 Cyclin A2 X51688 NM_001237 SEQ ID NO: 363 SEQ ID NO: 364 nucleoside phosphorylase X00737 NM_000270 SEQ ID NO: 365 SEQ ID NO: 366 TNF-related apoptosis inducing ligand TRAIL U37518 NM_003810 SEQ ID NO: 367 SEQ ID NO: 368 phosphodiesterase 4B, cAMP-specific L20971 NM_002600 SEQ ID NO: 369 SEQ ID NO: 370 nidogen (enactin) M30269 NM_002508 SEQ ID NO: 371 SEQ ID NO: 372 HYA22 protein D88153 NM_005808 SEQ ID NO: 373 SEQ ID NO: 374 phosphatidic acid phosphatase type 2A AF014402 NM_003711 SEQ ID NO: 375 SEQ ID NO: 376 KIAA0512, ALEX2 AB011084 NM_014782 SEQ ID NO: 377 SEQ ID NO: 378 thromboxane A2 receptor D38081 NM_001060 SEQ ID NO: 379 SEQ ID NO: 380 trefoil factor 3 (intestinal) AI985964 NM_003226 SEQ ID NO: 381 SEQ ID NO: 382 G-2 and S-phase expressed 1 AL031588 NM_016426 SEQ ID NO: 383 SEQ ID NO: 384 ADP-ribosyltransferase (NAD+; poly (ADP- AJ236876 NM_005484 SEQ ID NO: 385 SEQ ID NO: 386 ribose) polymerase)-like 2 serine/threonine kinase 12 AF015254 NM_004217 SEQ ID NO: 387 SEQ ID NO: 388 Tubulin, Alpha 1, Isoform 44 HG2259-HT2348 duplicate lamin B receptor L25931 NM_002296 SEQ ID NO: 389 SEQ ID NO: 390 KIAA0429 AB007889 NM_014751 SEQ ID NO: 391 SEQ ID NO: 392 transcription factor 4 M74719 NM_003199 SEQ ID NO: 393 SEQ ID NO: 394 syndecan 3 (N-syndecan), KIAA0468 AB007937 NM_014654 SEQ ID NO: 395 SEQ ID NO: 396 RECK protein precursor AA099265 NM_021111 SEQ ID NO: 397 SEQ ID NO: 398 Putative prostate cancer tumor suppressor U42349 NM_006765 SEQ ID NO: 399 SEQ ID NO: 400 protein phosphatase 1, regulatory (inhibitor) AB020630 SEQ ID NO: 401 SEQ ID NO: 402 subunit PDZ and LIM domain 1 (elfin) U90878 NM_020992 SEQ ID NO: 403 SEQ ID NO: 404 hypothetical protein from clone 643 AF091087 NM_020467 SEQ ID NO: 405 SEQ ID NO: 406 p53-regulated DDA3 AA926959 SEQ ID NO: 407 KIAA0062 D31887 SEQ ID NO: 408 SEQ ID NO: 409 medium-chain acyl-CoA dehydrogenase M91432 SEQ ID NO: 410 SEQ ID NO: 411 gap junction protein, alpha 1, 43 kD (connexin 43) M65188 NM_000165 SEQ ID NO: 412 SEQ ID NO: 413 MyoD family inhibitor U78313 NM_005586 SEQ ID NO: 414 SEQ ID NO: 415 endo/exonuclease Mre11 (MRE11A) AF073362 NM_005591 SEQ ID NO: 416 SEQ ID NO: 417 nuclear receptor subfamily 2, group F, member 1 X16155 NM_005654 SEQ ID NO: 418 SEQ ID NO: 419

TABLE 15 Sequence identifiers for sequences in Table 4 accession aa SEQ ID nt SEQ ID numbers NO: NO: p27 mRNA, interferon alpha- X67325 NM_005532 420 421 inducible protein 27 ribonuclease A (RNase A), D26129 NM_002933 422 423 pancreatic hematopoietic neural membrane U87947 NM_001425 424 425 protein (HNMP-1) N-cadherin M34064 NM_001792 426 427 N-cadherin M34064 NM_001792 duplicate interleukin 8 (IL8) M28130 NM_000584 428 429 interleukin 8, beta-thromboglobulin- M17017 NM_000584 430 431 like protein precursor tyrosine kinase receptor (axl) M76125 NM_001699 432 433 HG162-HT3165 duplicate cell surface glycoprotein CD44 L05424 434 435 (CD44) cell adhesion molecule (CD44) M59040 NM_000610 duplicate hyaluronate receptor (CD44) L05424 duplicate vascular endothelial growth factor U43142 NM_005429 436 437 related protein VRP, VEGF-C Vascular endothelial growth factor C X94216 NM_005429 duplicate collagen type XIII, alpha 1 M33653 NM_005203 438 439 (=COL4A2) collagen type XIII, alpha-1 M59217 NM_005203 duplicate collagen alpha-2 type I K01079 440 collagen alpha-2 type I K01079 duplicate collagen, type I, alpha 2 V00503 NM_000089 duplicate proteoglycan 1 X17042 NM_002727 441 442 phospholipase A2, group IV A, M72393 443 444 calcium-dependent phospholipid- binding protein (PLA2) carbohydrate (keratan sulfate Gal-6) AB003791 NM_003654 445 446 sulfotransferase tropomyosin 2 (beta), fibroblast M12125 NM_003289 447 448 tropomyosin chondroitin sulfate proteoglycan 2 X15998 NM_004385 449 450 (versican) chondroitin sulfate proteoglycan 2 X15998 NM_004385 duplicate (versican) latent transforming growth factor- Z37976 NM_000428 451 452 beta binding protein (LTBP-2) interleukin 6 (interferon, beta 2) X04430 NM_000600 453 454 bone morphogenetic protein-4 U43842 NM_001202 455 456 (hBMP-4) bone morphogenetic protein 2B, M22490 NM_001202 duplicate BMP-4 sarcolectin, keratin 7 AJ238246 NM_005556 457 458 neuronal cell adhesion molecule, AB002341 NM_005010 459 460 KIAA0343 neuronal cell adhesion molecule, U55258 NM_005010 duplicate hBRAVO/Nr-CAM precursor matrix metalloproteinase 1 M13509 NM_002421 461 462 (interstitial collagenase), skin collagenase stem cell factor, KIT ligand M59964 NM_000899 463 464 uPA X02419 NM_002658 465 466 plasminogen activator inhibitor-1 J03764 NM_000602 467 468 plasminogen activator inhibitor 1 M14083 NM_000602 duplicate selectin P, CD62, granule membrane M25322 NM_003005 469 470 protein-140 (GMP-140) precursor latrophilin-2 AJ131581 NM_012302 471 472 actin, alpha 2 X13839 NM_001613 473 474 fibroblast activation protein, alpha U09278 NM_004460 475 476 regulator of G-protein signalling 20 AF060877 NM_003702 477 478 IGF-II mRNA-binding protein 3 U97188 NM_006547 479 480 retina cDNA randomly primed W28438 481 sublibrary, EST brain acid-soluble protein 1, AF039656 NM_006317 482 483 neuronal tissue-enriched acidic protein (NAP-22) profilin 2 AL096719 NM_002628 484 485 profilin 2 L10678 NM_002628 duplicate Na,K-ATPase beta-1 subunit U16799 NM_001677 486 487 Claudin-7 AJ011497 NM_001307 488 489 normal gingiva U51712 490 a disintegrin and metalloproteinase AB009672 NM_003812 491 492 domain 23 COL8A1 mRNA for alpha 1(VIII) X57527 NM_001850 493 494 collagen signal transducer and activator of AF067575 495 496 transcription 6 (STAT6) transcription factor IL-4 Stat, U16031 NM_003153 duplicate STAT6 lipocortin-III, annexin A3 M20560 NM_005139 497 498 intercellular adhesion molecule 1 M24283 NM_000201 499 500 (CD54), major group rhinovirus receptor precusor solute carrier family 1 U08989 NM_004170 501 502 (neuronal/epithelial high affinity glutamate transporter, system Xag) solute carrier family 1 AI928365 NM_004170 duplicate (neuronal/epithelial high affinity glutamate transporter, system Xag) p53 inducible protein L47738 503 504 dihydropyrimidine dehydrogenase, U20938 NM_000110 505 506 DPYD natural killer cell transcript 4 AA631972 NM_004221 507 508 PFTAIRE protein kinase 1, AB020641 NM_012395 509 510 KIAA0834 RGP4, regulator of G-protein U27768 NM_005613 511 512 signalling 4 regulator of G-protein signalling 4 AI267373 NM_005613 duplicate Oncogene Amll-Evi-1, Fusion HG4058-HT4328 513 514 Activated Oncogene Amll-Evi-1, Fusion HG4058-HT4328 duplicate Activated adenylyl cyclase-associated protein 2 N90755 NM_006366 515 516 clusterin (complement lysis M25915 NM_001831 517 518 inhibitor, SP-40, 40, sulfated glycoprotein 2, apolipoprotein J) ADP ribosylation factor-like 7 AB016811 NM_005737 519 520 H factor (complement)-like 1 M65292 NM_002113 521 522 RNA helicase-related protein, H68340 NM_007372 523 524 metallothionein-If stimulated trans-acting factor (50 kDa) X82200 NM_006074 525 526 Staf50 cyclooxygenase-2 (hCox-2) U04636 NM_000963 527 528 GRO1 oncogene, melanoma growth X54489 NM_001511 529 530 stimulatory activity (MGSA) NRGN, neurogranin X99076 NM_006176 531 532 homologue of mouse dkk-1 AB020315 533 534 gastrointestinal tumor-associated J04152 NM_002353 535 536 antigen GA733-1, tumor-associated calcium signal transducer 2 laminin Z15008 NM_005562 537 538 transgelin, 22 kDa smooth muscle M95787 NM_003186 539 540 protein (SM22) JE gene encoding a monocyte M28225 541 542 secretory protein zinc finger protein 238, RP58 AJ223321 NM_006352 543 544 cathepsin C X87212 NM_001814 545 546 tissue-type plasminogen activator (t- M15518 NM_000930 547 548 PA) sushi-repeat protein AF060567 NM_014467 549 550 annexin A6 D00510 NM_001155 551 552 EphrinB1 U09303 NM_004429 553 554 EphrinB1 U09303 NM_004429 duplicate TFEC isoform (transcription factor D43945 NM_012252 555 556 EC) small inducible cytokine A2, M26683 NM_002982 557 558 (monocyte chemotactic protein1) small inducible cytokine A2 M26683 NM_002982 duplicate (monocyte chemotactic protein 1) endothelial cell protein C/APC L35545 NM_006404 559 560 receptor (EPCR) transglutaminase 2 (TGase) M55153 NM_004613 561 562 transglutaminase (TGase) M55153 NM_004613 duplicate human metallothionein-If M10943 563 564 transforming growth factor beta- M77349 NM_000358 565 566 induced (BIGH3) ENO2 gene for neuron specific X51956 567 568 (gamma) enolase FAT tumor suppressor (Drosophila) X87241 NM_005245 569 570 homolog malignant cell expression-enhanced S82470 NM_024298 571 572 gene/tumor progression-enhanced gene malignant cell expression-enhanced S82470 NM_024298 duplicate 574 gene/tumor progression-enhanced gene cDNA DKFZp566G0746 (from AL050078 575 clone DKFZp566G0746) lysyl oxidase-like 2 U89942 NM_002318 576 577 ras-related C3 botulinum toxin M64595 NM_002872 578 579 substrate 2 (rho family, small GTP binding protein Rac2) endothelial leukocyte adhesion M24736 NM_000450 580 581 molecule 1 (ELAM-1), selectin E laminin, alpha 5, KIAA0533 AB011105 582 583 placenta growth factor (PIGF) X54936 NM_002632 584 585 ALL1-fused gene from chromosome U16954 NM_006818 586 587 1q, AF1q stromelysin-2, MMP-10 X07820 NM_002425 588 589 metallothionein-I-A K01383 590 591 collagen VI alpha-1 X15880 592 593 mad protein homolog (hMAD-3) U68019 NM_005902 594 595 mad protein homolog (hMAD-3) U68019 NM_005902 duplicate mad protein homolog (hMAD-3) U68019 NM_005902 duplicate integral membrane protein 2A AL021786 596 interleukin 1 receptor-like 1 D12763 NM_003856 597 598 high-mobility group (nonhistone X92518 599 600 chromosomal) protein isoform I-C (HMGI-C) epidermal growth factor receptor U12535 NM_004447 601 602 kinase substrate (Eps8) lactate dehydrogenase B X13794 NM_002300 603 604 mRNA for unknown product D29810 605 606 hypothetical protein AL033377 607 DKFZp564D0462 lysyl hydroxylase isoform 2 U84573 NM_000935 608 609 (PLOD2) follistatin-like 3, follistatin-related U76702 NM_005860 610 611 protein (FLRG) Homo sapiens clone 24674 mRNA AF070578 612 sequence L-iditol-2 dehydrogenase L29254 613 614 neuronal pentraxin 1 U61849 NM_002522 615 616 hypothetical protein from clones U90908 NM_021226 617 618 23549 and 23762 UDP-N-acetylglucosamine AB011004 NM_003115 619 620 pyrophosphorylase zinc finger protein 185 (LIM Y09538 NM_007150 621 622 domain) four and a half LIM domains 2, U29332 NM_001450 623 624 heart protein (FHL-2) mitogen-activated protein kinase- U09578 NM_004635 625 626 activated protein kinase 3, MAPKAP kinase (3pK) metallothionein 1E (functional) R92331 627 TU3A protein AF035283 NM_007177 628 629 metallothionein 1H R93527 NM_005951 630 631 guanylate binding protein isoform II M55543 NM_004120 632 633 (GBP-2) soluble vascular endothelial cell U01134 NM_002019 634 635 growth factor receptor 1 (sVEGFR- 1) R-Ras M14949 636 637 R-ras M14949 638 639 creatine transporter (SLC6A8), U36341 NM_005629 640 641 solute carrier family 6, member 8 target of myb1 (chicken) homolog, Z82244 NM_005488 642 643 Heme Oxygenase 1 (HO-1) procollagen-lysine, 2-oxoglutarate L06419 NM_000302 644 645 5-dioxygenase, lysyl hydroxylase (PLOD) KIAA0836 AB020643 646 647 cDNA DKFZp434C171 (from clone AL080169 648 649 DKFZp434C171) IL-4-R mRNA for the interleukin 4 X52425 NM_000418 650 651 receptor chemokine (C—C motif) receptor- AF014958 NM_003965 652 653 like 2 (CCRL2), chemokine receptor X (CKRX) phospholipase C, beta 3 Z16411 NM_000932 654 655 (phosphatidylinositol-specific) LIM domain protein X93510 NM_003687 656 657 protein kinase (cAMP-dependent, M34181 NM_002731 658 659 catalytic) inhibitor beta rho GDP-dissociation Inhibitor 2 X69549 NM_001175 660 661 KIAA0975, imidazoline receptor AB023192 NM_007184 662 663 candidate poliovirus receptor X64116 NM_006505 664 665 poliovirus receptor X64116 NM_006505 duplicate immediate early response 3 S81914 NM_003897 666 667 metallothionein 2A AI547258 NM_005953 668 669 tropomyosin 1 (alpha) M19267 NM_000366 670 671 tropomyosin 1 (alpha) Z24727 NM_000366 duplicate tropomyosin 1 (alpha) M19267 NM_000366 duplicate TRAM-like protein D31762 NM_012288 672 673 E3 ubiquitin ligase SMURF2 AA630312 NM_022739 674 675 EGF-containing fibulin-like U03877 NM_004105 676 677 extracellular matrix protein 1 G protein-coupled receptor 56 AJ011001 NM_005682 678 679 c-jun proto oncogene (JUN) J04111 NM_002228 680 681 regulator of G-protein signalling 10, AF045229 NM_002925 682 683 RGS10 amyloid beta (A4) precursor U62325 684 685 protein-binding, family B, member 2 (Fe65-like) ras-related rho protein M12174 NM_004040 686 687 proteasome (prosome, macropain) AL031177 NM_002814 688 689 26S subunit, non-ATPase, 10 KIAA0537 AB011109 NM_014840 690 691 lysosome-associated membrane X77196 NM_002294 692 693 protein-2 phospholipid transfer protein L26232 NM_006227 694 695 N-myristoyltransferase 2 AF043325 NM_004808 696 697 phosphofructokinase (PFKM) U24183 NM_000289 698 699 integrin, beta 4 X53587 NM_000213 700 701 leupaxin AF062075 NM_004811 702 703 endothelin-converting-enzyme 1 Z35307 NM_001397 704 705 wild-type p53 activated fragment-1 U03106 NM_000389 706 707 (WAF1), cyclin-dependent kinase inhibitor 1A (p21, Cip1) ICAM-2, cell adhesion ligand for X15606 NM_000873 708 709 LFA-1 ICAM-2, cell adhesion ligand for X15606 NM_000873 duplicate LFA-1 intercellular adhesion molecule 2 M32334 710 711 (ICAM-2) eukaryotic translation initiation AF035280 NM_014239 712 713 factor 2B, eIF-2B beta subunit uridine phosphorylase X90858 NM_003364 714 715 integrin, beta 5 X53002 NM_002213 716 717 N-sulfoglucosamine sulfohydrolase U30894 NM_000199 718 719 (sulfamidase) synaptojanin 2 AF039945 720 721 metallothionein 1L AA224832 NM_002450 722 723 macrophage capping protein, M94345 NM_001747 724 725 gelsolin-like HSPC022 protein W68830 NM_014029 726 727 Human clone 137308 mRNA, AW006742 no 728 partial cds protocadherin 42, PC42, L11370 NM_002587 729 730 protocadherin 1 (cadherin-like 1) caspase-like apoptosis regulatory AF005775 NM_003879 731 732 protein 2 (CLARP2) caspase-like apoptosis regulatory AF005775 NM_003879 duplicate protein 2 (CLARP2) major vault protein, lrp X79882 NM_005115 733 734 Fanconi anemia, complementation AC004472 NM_004629 735 736 group G prion protein (PrP) U29185 NM_000311 737 738 interferon-stimulated protein, 15 kDa AA203213 NM_005101 739 740 serine (or cysteine) proteinase L40377 NM_002640 741 742 inhibitor, clade B (ovalbumin), cytoplasmic antiproteinase 2 (CAP2) biglycan J04599 NM_001711 743 744 chemokine (C—X—C motif), receptor L06797 NM_003467 745 746 4 (fusin) ubiquitin carboxyl-terminal esterase X04741 NM_004181 747 748 L1 (ubiquitin thiolesterase) KIAA0469 AB007938 NM_014851 749 750 TNF (ligand) superfamily, member AL022310 NM_003326 751 752 4 (tax-transcriptionally activated glycoprotein 1, 34 kD) KIAA1053 AB028976 753 754 NAD(P)H-quinone oxireductase M81600 755 756 sushi-repeat-containing protein U61374 NM_006307 757 758 integrin, alpha 5 X06256 NM_002205 759 760 enigma (LIM domain protein) L35240 NM_005451 761 762 ectonucleoside triphosphate AJ133133 NM_001776 763 764 diphosphohydrolase 1 transforming growth factor-beta M60315 NM_001718 765 766 (tgf-beta), bone morphogenetic protein 6 transforming growth factor-beta M60315 NM_001718 duplicate (tgf-beta), bone morphogenetic protein 6 nicotinamide N-methyltransferase, U08021 NM_006169 767 768 NNMT cDNA DKFZp564J0323 (from AL049957 no 769 clone DKFZp564J0323) thioredoxin reductase beta AB019694 NM_006440 770 771 f-box and leucine-rich repeat protein 2 AL049953 772 773 transcobalamin II (TCN2) L02648 NM_000355 774 775 aldehyde dehydrogenase 2, X05409 NM_000690 776 777 mitochondrial GTP-binding protein ragB X90530 NM_006064 778 779 lymphocyte antigen 75 AF011333 NM_002349 780 781 GM2 activator protein X62078 782 783 type 3 inositol 1,4,5-trisphosphate U01062 NM_002224 784 785 receptor (ITPR3) KIAA0284 AI828210 no 786 metallothionein I-B M13485 787 788 BTG2 U72649 NM_006763 789 790 adenylate kinase 1 J04809 NM_000476 791 792 tumor necrosis factor receptor Y09392 NM_003790 793 794 superfamily, member 12, WSL-LR, WSL-S1 and WSL-S2 proteins aminopeptidase N/CD13 M22324 NM_001150 795 796 growth arrest and DNA-damage- M60974 NM_001924 797 798 inducible protein (gadd45) KIAA0638 protein AB014538 799 800 vinculin M33308 NM_003373 801 802 procollagen-proline, 2-oxoglutarate U90441 NM_004199 803 804 4-dioxygenase (proline 4- hydroxlase), alpha polypeptide II msg1-related gene 1 (mrg1), U65093 NM_006079 805 806 Cbp/p300-interacting transactivator microsomal glutathione S- AF026977 NM_004528 807 808 transferase 3 vitamin A responsive; cytoskeleton AF070523 NM_006407 809 810 related 17-kDa protein, interferon- M13755 NM_005101 811 812 stimulated protein, 15 kDa matrix metalloproteinase 14 X83535 NM_004995 813 814 (membrane-inserted) 4F2 cell-surface antigen, solute J02939 NM_002394 815 816 carrier family 3, member 2 metallothionein-III M93311 NM_005954 817 818 protein kinase (cAMP-dependent, S76965 NM_006823 819 820 catalytic) inhibitor alpha protein kinase (cAMP-dependent, S76965 NM_006823 duplicate catalytic) inhibitor alpha reticulocalbin 1, EF-hand calcium D42073 NM_002901 821 822 binding domain lipin 1, KIAA0188 D80010 823 824 protease, serine, 23 AF015287 NM_007173 825 826 hect domain and RLD 2 AF041080 NM_004667 827 828 GATA-binding protein (GATA2) M68891 NM_002050 829 830 agrin precursor AF016903 831 832 equilibrative nucleoside transporter U81375 NM_004955 833 834 1 (hENT1) coronin, actin-binding protein 2B, AB023142 835 836 KIAA0925 f-box and WD-40 domain protein 3 U07000 NM_012165 837 838 nonsyndromic hearing impairment AF073308 NM_004403 839 840 protein (DFNA5) actin filament associated protein D25248 NM_021638 841 842 TNFR-related death receptor-6 AF068868 NM_014452 843 844 (DR6) serum/glucocorticoid regulated Y10032 NM_005627 845 846 kinase DNase X X90392 NM_006730 847 848 DNase X X90392 NM_006730 duplicate fatty acid desaturase 3 AC004770 NM_021727 849 850 LYL-1 M22637 851 852 ATP-binding cassette, sub-family C X78338 NM_004996 853 854 (CFTR/MRP), member 1 transmembrane protein (CD59) M84349 855 856 fms-related tyrosine kinase 1, S77812 857 858 VEGFR-1 Hypothetical protein FLJ23403 AI681538 NM_022068 859 860 hypothetical protein FLJ20898 AI733570 NM_024600 861 862 

1. A method for differentially modulating the growth or differentiation of blood endothelial cells (BEC) or lymphatic endothelial cells (LEC), comprising contacting endothelial cells with a composition comprising an agent that differentially modulates blood or lymphatic endothelial cells, said agent selected from the group consisting of: (a) a polypeptide that comprises an amino acid sequence of a BEC polypeptide or a LEC polypeptide, or an active fragment of said polypeptide; (b) a polynucleotide that comprises a nucleotide sequence that encodes a polypeptide according to (a); (c) an antibody that specifically binds to a polypeptide according to (a); (d) a polypeptide comprising a fragment of the-antibody of (c), wherein the fragment and the antibody bind to the polypeptide; (e) an antisense nucleic acid to a human gene or mRNA encoding the polypeptide of (a); (f) an interfering RNA (RNAi) to a human gene or mRNA encoding the polypeptide of (a).
 2. A method according to claim 1, wherein the endothelial cells are contacted with the composition ex vivo.
 3. A method according to claim 1, wherein the composition comprises a pharmaceutically acceptable diluent, adjuvant, or carrier, and the contacting step comprises administering the composition to a mammalian subject to differentially modulate BECs or LECs in the mammalian subject.
 4. A method according to claim 3, comprising: identifying a human subject with a disorder characterized by hyperproliferation of LECs; and administering to the human subject the composition, wherein the agent differentially inhibits LEC growth compared to BEC growth.
 5. A method according to claim 3, comprising: identifying a human subject with a disorder characterized by hyperproliferation of LECs; screening LECs of the subject to identify overexpression of a polypeptide set forth in Table 3; and administering to the human subject the composition, wherein the agent differentially inhibits LEC growth compared to BEC growth by inhibiting expression of the polypeptide identified by the screening step.
 6. A method according to claim 3 of modulating the growth of lymphatic endothelial cells in a human subject, comprising steps of: identifying a human subject with a hypoproliferative lymphatic disorder; screening the subject to identify underexpression or underactivity of a LEC polypeptide set forth in Table 3, wherein said protein is not set forth in Table 1 or 2; administering to the human subject said composition, wherein the agent comprises the LEC polypeptide (a) identified by the screening step or an active fragment of said polypeptide, or comprises the polynucleotide (b) that comprises a nucleotide sequence that encodes the polypeptide.
 7. Use of an agent for the manufacture of a medicament for the differential modulation of blood vessel endothelial cell (BEC) or lymphatic vessel endothelial cell (LEC) growth or differentiation, said agent selected from the group consisting of: (a) a polypeptide that comprises an amino acid sequence of a BEC polypeptide or a LEC polypeptide, or an active fragment of said polypeptide; (b) a polynucleotide that comprises a nucleotide sequence that encodes a polypeptide according to (a); (c) an antibody that specifically binds to a polypeptide according to (a); (d) a polypeptide comprising a fragment of the antibody of (c), wherein the fragment and the antibody bind to the polypeptide; (e) an antisense nucleic acid to a human gene or mRNA encoding the polypeptide of (a); (f) an interfering RNA (RNAi) to a human gene or mRNA encoding the polypeptide of (a).
 8. A method or use according to claim 1, wherein the polypeptide is a LEC polypeptide selected from the LEC polypeptides set forth in Table 3, and the agent differentially modulates LEC growth or differentiation over BEC growth or differentiation.
 9. A method or use according to claim 1, wherein the polypeptide is a BEC polypeptide selected from the BEC polypeptides set forth in Table 4, and the agent differentially modulates BEC growth or differentiation over LEC growth or differentiation.
 10. A method or use according to claim 8, wherein the polypeptide is not set forth in Tables 1 or
 2. 11. A method or use according to claim 8, wherein the LEC polypeptide comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 81, 187, 207, 211, 221, 235, 241, 293, and
 391. 12. A method or use according to claim 8, wherein the LEC polypeptide comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 31-34, 46, and
 48. 13. A method or use according to claim 12, wherein the agent comprises an antibody according to (c) or polypeptide according to (d).
 14. A method according to claim 12, wherein the agent comprises an extracellular domain fragment of the polypeptide of (a), or a polynucleotide encoding said extracellular domain fragment.
 15. A method or use according to claim 1, wherein the agent comprises an antisense molecule.
 16. A method of treating hereditary lymphedema comprising: identifying a human subject with lymphedema and with a mutation in at least one allele of a gene encoding a LEC protein identified in Table 3, wherein the mutation correlates with lymphedema in human subjects, and with the proviso that said LEC protein is not VEGFR-3; and administering to said subject a composition comprising a lymphatic growth agent selected from the group consisting of VEGF-C polypeptides, VEGF-D polypeptides, VEGF-C polynucleotides, and VEGF-D polynucleotides.
 17. Use of a lymphatic growth agent selected from the group consisting of VEGF-C polypeptides, VEGF-D polypeptides, VEGF-C polynucleotides, and VEGF-D polynucleotides in the manufacture of a medicament for the treatment of hereditary lymphedema resulting from a mutation in a LEC gene identified in Table 3, with the proviso that said gene is not VEGFR-3.
 18. A method of screening for an endothelial cell disorder or predisposition to said disorder, comprising obtaining a biological sample containing endothelial cell mRNA from a human subject; and measuring expression of a BEC or LEC gene from the amount of mRNA in the sample transcribed from said gene, wherein the BEC or LEC gene encodes a polypeptide identified in Table 3 or
 4. 19. A method of monitoring the efficacy or toxicity of a drug on endothelial cells, comprising steps of: measuring expression of at least one BEC or LEC gene in endothelial cells of a mammalian subject before and after administering a drug to the subject, wherein the at least one BEC or LEC gene encodes a polypeptide set forth in Table 3 or Table 4, and wherein changes in expression of the BEC or LEC gene correlates with efficacy or toxicity of the drug on endothelial cells.
 20. A method of identifying compounds that modulate growth of endothelial cells, comprising culturing endothelial cells in the presence and absence of a compound; and measuring expression of at least one BEC or LEC gene in the cells, wherein the BEC or LEC gene is selected from the genes encoding polypeptides set forth in Tables 3 and 4, wherein a change in expression of at least one BEC gene in the presence compared to the absence of the compound identifies the compound as a modulator of BEC growth, and wherein a change in expression of at least one LEC gene in the presence compared to the absence of the compound identifies the compound as a modulator of LEC growth.
 21. A method according to claim 20 of screening for a compound that selectively modulates BEC or LEC growth or differentiation, wherein the measuring step comprises measuring expression of at least one BEC gene and at least one LEC gene in the cells, and wherein the method comprises screening for a compound that selectively modulates BEC or LEC growth or differentiation by selecting a compound that differentially modulates expression of the at least one BEC gene compared to expression of the at least one LEC gene.
 22. A composition comprising an isolated polynucleotide that comprises a nucleotide sequence that encodes a polypeptide comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 31-44, 46, 48, 50, 52, 81, 187, 207, 211, 221, 235, 241, 293, and 391; and a pharmaceutically acceptable diluent, carrier or adjuvant.
 23. A composition according to claim 22, comprising a polynucleotide that comprises a nucleotide sequence selected from the group consisting of SEQ ID NOS: 14-30, 45, 47, 49, 51, 82, 93, 111, 188, 208, 212, 222, 236, 242, 294, and 392, or a fragment thereof that encodes the polypeptide.
 24. An expression vector comprising an expression control sequence operably linked to a polynucleotide that comprises a nucleotide sequence that encodes a polypeptide comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 31-44, 46, 48, 50, 52, 81, 187, 207, 211, 221, 235, 241, 293, and
 391. 25. An expression vector according to claim 24 that is a replication-deficient adenoviral or adeno-associated viral vector containing the polynucleotide.
 26. A composition comprising an expression vector according to claim 24 and a pharmaceutically acceptable diluent, carrier, or adjuvant.
 27. A kit comprising the composition according to claim 22 packaged with a protocol for administering the composition to a mammalian subject to modulate the lymphatic system in said subject.
 28. A host cell transformed or transfected with an expression vector according to claim
 24. 29. A method for producing a LEC polypeptide comprising steps of growing a host cell according to claim 28 under conditions in which the cell expresses the polypeptide encoded by the polynucleotide.
 30. A purified and isolated polypeptide comprising an amino acid sequence selected from the group consisting of SEQ ID NOS: 31-44, 46, 48, 50, 52, 81, 187, 207, 211, 221, 235, 241, 293, and
 391. 31. A purified and isolated polypeptide comprising an amino acid sequence selected from the group consisting of: (a) SEQ ID NOS: 31-34, 46, 48, 207, 676, 859, and 861; and (b) an extracellular domain fragment of at least 10 amino acids of an amino acid sequence of (a).
 32. A purified and isolated, soluble polypeptide according to claim 31 comprising an extracellular domain fragment of an amino acid sequence selected from the group consisting of: SEQ ID NOS: 31-34, 46, 48, 207, 676, 859, and 861, wherein the polypeptide lacks any transmembrane domain.
 33. A polypeptide according to claim 32 that lacks any intracellular domain.
 34. A fusion protein comprising a polypeptide according to claim 32 fused to an immunoglobulin fragment comprising an immunoglobulin constant region.
 35. A composition comprising a polypeptide or protein according to claim 30 and a pharmaceutically acceptable diluent, carrier or adjuvant.
 36. A kit comprising the composition according to claim 35 and a protocol for administering said pharmaceutical composition to a mammalian subject to modulate the lymphatic system in said subject.
 37. An antibody that specifically binds to a polypeptide according to claim
 30. 38. An antibody according to claim 37 that is a humanized antibody.
 39. A protein comprising an antigen binding domain of an antibody that specifically binds-to a polypeptide according to claim 30, wherein said protein specifically binds to said polypeptide.
 40. A method of identifying a LEC nucleic acid comprising: (a) contacting a biological sample containing a candidate LEC nucleic acid with a polynucleotide comprising a fragment of at least 14 contiguous nucleotides of a sequence selected from the group consisting of SEQ ID NOS:1-30, 45, 47, 49, 51, 82, 93, 111, 188, 208, 212, 236, 242, 294, and 392, or a complement thereof, under the following stringent hybridization conditions: (i) hybridization at 42° C. for 20 hours in a solution containing 50% formamide, 5×SSPE, 5× Denhardt's solution, 0.1% SDS and 0.1 mg/ml denatured salmon sperm DNA, and (ii) washing for 30 minutes at 65° C. in 1×SSC, 0.1% SDS; and (b) detecting hybridization of said candidate LEC nucleic acid and said polynucleotide, thereby identifying a LEC nucleic acid.
 41. A method of identifying a LEC protein comprising: (a) contacting a biological sample containing a candidate LEC protein with a LEC protein binding partner selected from the group consisting of an antibody according to claim 37, under conditions suitable for binding therebetween; and (b) detecting binding between said candidate LEC protein and said LEC binding partner, thereby identifying a LEC protein.
 42. A method of identifying a LEC comprising: (a) contacting a biological sample comprising cells with a LEC binding partner under conditions suitable for binding therebetween, wherein said LEC binding partner comprises an antibody that binds to a polypeptide comprising a sequence selected from the group consisting of SEQ ID NOS:31-34, 46, 48, 207, 676, 859, and 861, or comprises an antigen binding fragment of said antibody; and (b) identifying a LEC by detecting binding between a cell and said LEC binding partner, where binding of the LEC binding partner to the cell identifies a LEC.
 43. A method of assaying for risk of developing hereditary lymphedema, comprising. (a) assaying nucleic acid of a human subject for a mutation that correlates with a hereditary lymphedema phenotype and alters the encoded amino acid sequence of at least one gene allele of the human subject when compared to the amino acid sequence of the polypeptide encoded by a corresponding wild-type gene allele, wherein the wild-type polypeptide is a polypeptide identified in Table
 3. 44. A method of assaying for risk of developing hereditary lymphedema, comprising (a) assaying nucleic acid of a human subject for a mutation that correlates with a hereditary lymphedema phenotype and alters the encoded amino acid sequence of at least one gene allele of the human subject when compared to the amino acid sequence of the polypeptide encoded by a corresponding wild-type gene allele, wherein the wild-type polypeptide comprises an amino acid sequence selected from the group consisting of SEQ ID NOS: 31-44, 46, 48, 52, 54, 207, 676, 859, and 861; (b) correlating the presence or absence of said mutation in the nucleic acid to a risk of developing hereditary lymphedema, wherein the presence of said mutation in the nucleic acid correlates with an increased risk of developing hereditary lymphedema, and wherein the absence of said mutation in the nucleic acid correlates with no increased risk of developing hereditary lymphedema.
 45. A method of assaying for risk of developing hereditary lymphedema, comprising (a) assaying nucleic acid of a human subject for a mutation that alters the encoded amino-acid sequence of at least one transcription factor allele of the human subject and alters transcription modulation activity of the transcription factor polypeptide encoded by the allele, when compared to the transcription modulation activity of a transcription factor polypeptide encoded by a wild-type allele, wherein the wild-type transcription factor polypeptide comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 81, SEQ ID NO: 211, SEQ ID NO: 241, and transcription factors encoded by sequences in Table 5; and (b) correlating the presence or absence of said mutation in the nucleic acid to a risk of developing hereditary lymphedema, wherein the presence of said mutation in the nucleic acid correlates with an increased risk of developing hereditary lymphedema, and wherein the absence of said mutation in the nucleic acid correlates with no increased risk of developing hereditary lymphedema.
 46. The method according to claim 45 wherein said wild-type transcription factor allele comprises the Sox18 amino acid sequence set forth as SEQ ID NO:54.
 47. The method according to claim 46 wherein the assaying identifies a mutation altering a transactivating or DNA binding domain amino acid sequence of the protein encoded by the Sox18 allele.
 48. The method according to claim 46, wherein said mutation reduces transcriptional activation of a SOX18-responsive gene compared to transcriptional activation of said gene by wild-type SOX18.
 49. A method of assaying for risk of developing hereditary lymphedema, comprising (a) assaying nucleic acid of a human subject for a mutation that alters the encoded amino acid sequence of at least one LEC gene allele of the human subject and alters the, binding affinity of the adhesion polypeptide encoded by the LEC gene allele, when compared to the binding affinity of an adhesion polypeptide encoded by a wild-type allele, wherein the wild-type adhesion polypeptide comprises an amino acid sequence selected from the group consisting of SEQ ID NOS:31-34, 46, 207, 676, 859, and 861; and (b) correlating the presence or absence of said mutation in the nucleic acid to a risk of developing hereditary lymphedema, wherein the presence of said mutation in the nucleic acid correlates with an increased risk of developing hereditary lymphedema, and wherein the absence of said mutation in the nucleic acid correlates with no increased risk of developing hereditary lymphedema.
 50. The method according to claim 43, wherein the assaying identifies the presence of the mutation, and the correlating step identifies the increased risk of said patient developing hereditary lymphedema.
 51. A method of screening a human subject for an increased risk of developing hereditary lymphedema comprising assaying nucleic acid of a human subject for a mutation that alters the encoded amino acid sequence of at least one polypeptide comprising an amino acid sequence of Table
 3. 52. A method of claim 51, wherein the polypeptide comprises an amino acid sequence selected from the group consisting of SEQ ID NOS: 31-44, 46, 48, 50, 52, and 54, 207, 676, 859, and 861 in a manner that correlates with the risk of developing hereditary lymphedema.
 53. The method according to claim 52 wherein the polypeptide comprises the SOX18 amino acid sequence set forth in SEQ ID NO:
 54. 54. The method according to claim 43 wherein said method comprises at least one procedure selected from the group consisting of: (a) determining a nucleotide sequence of at least one codon of at least one polynucleotide of the human subject; (b) performing a hybridization assay: to determine whether nucleic acid from the human subject has a nucleotide sequence identical to or different from one or more reference sequences; (c) performing a polynucleotide migration assay to determine whether nucleic acid from the-human subject has a nucleotide sequence identical to or different from one or more reference sequences; and (d) performing a restriction endonuclease digestion to determine whether nucleic acid from the human subject has a nucleotide sequence identical to or different from one or more reference sequences.
 55. The method according to claim 43 wherein said method comprises: performing a polymerase chain reaction (PCR) to amplify nucleic acid comprising the coding sequence of said LEC polynucleotide, and determining nucleotide sequence of the amplified nucleic acid.
 56. A method of screening for a hereditary lymphedema genotype in a human subject, comprising: (a) providing a biological sample comprising nucleic acid from said subject, and (b) analyzing said nucleic acid for the presence of a mutation altering the encoded amino acid sequence of the at least one allele of at least one gene in the human subject relative to a human gene encoding an amino acid sequence selected from the group consisting of SEQ ID NOs: 31-44, 46, 48, 50, 52, 54, 207, 676, 859, and 861, wherein the presence of a mutation altering the encoded amino acid sequence in the human subject in a manner that correlates with lymphedema in human subjects identifies a hereditary lymphedema genotype.
 57. The method according to claim 56 wherein said biological sample is a cell sample.
 58. The method according to claim 56 wherein said analyzing comprises sequencing a portion of said nucleic acid.
 59. The method according to claim 56 wherein the human subject has a hereditary lymphedema genotype identified by the method of screening.
 60. The method according to claim 49, wherein the at least one gene corresponds to the human Sox18 gene that encodes the amino acid sequence set forth in SEQ ID NO:
 54. 61. A method of inhibiting lymphangiogenesis comprising administering to a subject an inhibitor of a LEC transmembrane polypeptide, wherein the LEC transmembrane polypeptide comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 31-34, 46 48, 207, 676, 859, and 861, and wherein the inhibitor is selected from the group consisting of (a) a soluble extracellular domain fragment of the LEC transmembrane polypeptide; (b) an antibody that binds to the extracellular domain of the LEC transmembrane polypeptide; (c) a polypeptide comprising an antigen binding domain of the antibody according to (b); and (d) an antisense nucleic acid complementary to the nucleic acid encoding the LEC transmembrane polypeptide or its complement.
 62. A method according to claim 61, wherein the inhibitor is a polypeptide comprising an extracellular domain fragment of an LEC polypeptide, wherein the sequence of said extracellular domain is selected from the group consisting of amino acids 1-152 of SEQ ID NO:31, amino acids 1-695 of SEQ ID NO:32 and amino acids 1-248 of SEQ ID NO:33.
 63. The method according to claim 61 wherein said subject is a human containing a tumor.
 64. A method for modulating lymphangiogenesis in a mammalian subject comprising: administering to a mammalian subject in need of modulation of lymphangiogenesis an antisense molecule to a LEC polynucleotide, in an amount effective to inhibit transcription or translation of the polypeptide encoded by the LEC polynucleotide, wherein the LEC polynucleotide comprises a nucleotide sequence selected from the group consisting of SEQ ID NOS: 14-30, 45, 47, 49, AND 51, 208, 677, 860, and
 862. 65. A method of treating hereditary lymphedema, comprising: (a) identifying a human subject with hereditary lymphedema and with a mutation that alters the encoded amino acid sequence of at least one polypeptide of the human subject, relative to the amino acid sequence of a polypeptide comprising an amino acid sequence selected from the group consisting of SEQ ID NOS: 31-44, 46, 48, 50, 52, 54, 207, 676, 859, and 861; and (b) administering to said subject a lymphatic growth factor selected from the group consisting of a VEGF-C polynucleotide, a VEGF-C polypeptide, a VEGF-D polynucleotide, and a VEGF-D polypeptide.
 66. A method of modulating the growth of endothelial cells or endothelial precursor cells, comprising contacting endothelial cells or endothelial precursor cells with a composition comprising an agent the modulates prox-1 transcription regulation in the cells, wherein the agent is selected from the group consisting of: (a) a prox-1 polypeptide; (b) a polynucleotide encoding a prox-1 polypeptide; (c) an antisense molecule to prox-1.
 67. A method according to claim 66, wherein the cells comprises cultured endothelial cells or endothelial precursor cells, and the contacting is performed ex vivo.
 68. A method according to claim 67, wherein the contacting comprises including the agent in the culture medium.
 69. A method according to claim 66, wherein the cells comprise endothelial precursor cells.
 70. A method according to claim 66, wherein the cells are introduced into a mammalian subject after the contacting step.
 71. A method according to claim 70, wherein the subject is human.
 72. A method according to claim 71, wherein the human subject has a LEC disorder.
 73. A method of increasing LEC function in a human subject, comprising: isolating endothelial cells or endothelial precursor cells from a human subject; transforming or transfecting the endothelial cells with an expression vector comprising a nucleotide sequence encoding a prox-1 polypeptide, to promote LEC differentiation and growth; and administering the LEC cells to a human subject after the transforming or transfecting step.
 74. A method according to claim 73, wherein the human subject of the isolating and administering steps is the same.
 75. A method according to claim 73, wherein the human subject has lymphedema.
 76. A method according to claim 73, wherein the vector and transforming or transfecting method are selected for transient expression of the prox-1.
 77. A method according to claim 73, wherein the expression vector comprises a replication-deficient adenoviral vector.
 78. An isolated polypeptide comprising an amino acid sequence at least 95% identical to amino acids 61-127 of SEQ ID NO:
 31. 79. A polypeptide according to claim 78, comprising an amino acid sequence at least 95% identical to amino acids 30-152 of SEQ ID NO:
 31. 80. A soluble polypeptide comprising a fragment of the amino acid sequence set forth in SEQ ID NO: 31, wherein said fragment lacks the transmembrane and intracellular amino acids of SEQ ID NO:
 31. 81. An isolated polypeptide comprising at least one leucine-rich region of SEQ ID NO:
 32. 82. An isolated polypeptide according to claim 81, wherein the polypeptide lacks transmembrane amino acids of SEQ ID NO:
 32. 83. An isolated polypeptide comprising at least one leucine-rich region of SEQ ID NO:
 33. 84. An isolated polypeptide according to claim 81, wherein the polypeptide lacks transmembrane amino acids of SEQ ID NO:
 33. 85. An isolated polypeptide comprising an amino acid sequence at least 95% identical to a fragment of a polypeptide comprising the amino acid sequence set forth in SEQ ID NO: 111, wherein said fragment includes at least one thrombospondin type I repeat sequence.
 86. An isolated polypeptide according to claim 85, wherein said fragment includes the six thrombospondin type I repeat sequences of SEQ ID NO:
 111. 87. An isolated polypeptide comprising an amino acid sequence at least 95% identical to a fragment of a polypeptide comprising the amino acid sequence set forth in SEQ ID NO: 111, wherein said fragment includes at least one immunoglobulin C-2 type domain.
 88. An isolated polypeptide according to claim 85, wherein said fragment includes the three immunoglobulin C-2 type domain sequences of SEQ ID NO:
 111. 89. A fusion protein comprising a polypeptide according to claim 78 and a heterologous polypeptide.
 90. An antibody that specifically binds to a polypeptide according to claim
 78. 91. A polynucleotide comprising a nucleotide sequence that encodes a polypeptide according to claim
 78. 92. An expression vector comprising a polynucleotide according to claim 91 operatively linked to an expression control sequence.
 93. An expression vector according to claim 92 that is a replication deficient adenoviral vector.
 94. A method or use according to claim 9, wherein the polypeptide is not set forth in Tables 1 or
 2. 95. A method or use according to claim 1, wherein the agent comprises an antisense molecule, and wherein the polypeptide is not set forth in Tables 1 or
 2. 96. The method according to claim 43, wherein the assaying identifies the presence of the mutation, and the correlating step identifies the increased risk of said patient developing hereditary lymphedema, and wherein said method comprises at least one procedure selected from the group consisting of: (a) determining a nucleotide sequence of at least one codon of at least one polynucleotide of the human subject; (b) performing a hybridization assay to determine whether nucleic acid from the human subject has a nucleotide sequence identical to or different from one or more reference sequences; (c) performing a polynucleotide migration assay to determine whether nucleic acid from the human subject has a nucleotide sequence identical to or different from one or more reference sequences; and (d) performing a restriction endonuclease digestion to determine whether nucleic acid from the human subject has a nucleotide sequence identical to or different from one or more reference sequences.
 97. The method according to claim 43, wherein the assaying identifies the presence of the mutation, and the correlating step identifies the increased risk of said patient developing hereditary lymphedema, wherein said method comprises: performing a polymerase chain reaction (PCR) to amplify nucleic acid comprising the coding sequence of said LEC polynucleotide, and determining nucleotide sequence of the amplified nucleic acid
 98. A method according to claim 73, wherein the human subject has lymphedema, and wherein the vector and transforming or transfecting method are selected for transient expression of the prox-1.
 99. A method according to claim 73, wherein the human subject has lymphedema, and wherein the expression vector comprises a replication-deficient adenoviral vector. 